diff --git a/core/modules/aggregator/src/Plugin/views/field/TitleLink.php b/core/modules/aggregator/src/Plugin/views/field/TitleLink.php
index 9ab50bf..d768109 100644
--- a/core/modules/aggregator/src/Plugin/views/field/TitleLink.php
+++ b/core/modules/aggregator/src/Plugin/views/field/TitleLink.php
@@ -29,7 +29,7 @@ class TitleLink extends FieldPluginBase {
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields['link'] = 'link';
+    $this->additionalFields['link'] = 'link';
   }
 
   /**
diff --git a/core/modules/comment/src/Plugin/views/field/Comment.php b/core/modules/comment/src/Plugin/views/field/Comment.php
index 25c001d..128f845 100644
--- a/core/modules/comment/src/Plugin/views/field/Comment.php
+++ b/core/modules/comment/src/Plugin/views/field/Comment.php
@@ -38,12 +38,12 @@ public function init(ViewExecutable $view, DisplayPluginBase $display, array &$o
     parent::init($view, $display, $options);
 
     if (!empty($this->options['link_to_comment'])) {
-      $this->additional_fields['cid'] = 'cid';
-      $this->additional_fields['entity_id'] = array(
+      $this->additionalFields['cid'] = 'cid';
+      $this->additionalFields['entity_id'] = array(
         'table' => 'comment_field_data',
         'field' => 'entity_id'
       );
-      $this->additional_fields['entity_type'] = array(
+      $this->additionalFields['entity_type'] = array(
         'table' => 'comment_field_data',
         'field' => 'entity_type'
       );
diff --git a/core/modules/comment/src/Plugin/views/field/LastTimestamp.php b/core/modules/comment/src/Plugin/views/field/LastTimestamp.php
index 62aabf0..61b45c7 100644
--- a/core/modules/comment/src/Plugin/views/field/LastTimestamp.php
+++ b/core/modules/comment/src/Plugin/views/field/LastTimestamp.php
@@ -27,7 +27,7 @@ class LastTimestamp extends Date {
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields['comment_count'] = 'comment_count';
+    $this->additionalFields['comment_count'] = 'comment_count';
   }
 
   /**
diff --git a/core/modules/comment/src/Plugin/views/field/NodeNewComments.php b/core/modules/comment/src/Plugin/views/field/NodeNewComments.php
index 748291b..ee43935 100644
--- a/core/modules/comment/src/Plugin/views/field/NodeNewComments.php
+++ b/core/modules/comment/src/Plugin/views/field/NodeNewComments.php
@@ -70,9 +70,9 @@ public static function create(ContainerInterface $container, array $configuratio
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields['entity_id'] = 'nid';
-    $this->additional_fields['type'] = 'type';
-    $this->additional_fields['comment_count'] = array('table' => 'comment_entity_statistics', 'field' => 'comment_count');
+    $this->additionalFields['entity_id'] = 'nid';
+    $this->additionalFields['type'] = 'type';
+    $this->additionalFields['comment_count'] = array('table' => 'comment_entity_statistics', 'field' => 'comment_count');
   }
 
   protected function defineOptions() {
@@ -97,7 +97,7 @@ public function buildOptionsForm(&$form, FormStateInterface $form_state) {
   public function query() {
     $this->ensureMyTable();
     $this->addAdditionalFields();
-    $this->field_alias = $this->table . '_' . $this->field;
+    $this->fieldAlias = $this->table . '_' . $this->field;
   }
 
   public function preRender(&$values) {
@@ -110,7 +110,7 @@ public function preRender(&$values) {
     $ids = array();
     foreach ($values as $id => $result) {
       $nids[] = $result->{$this->aliases['nid']};
-      $values[$id]->{$this->field_alias} = 0;
+      $values[$id]->{$this->fieldAlias} = 0;
       // Create a reference so we can find this record in the values again.
       if (empty($ids[$result->{$this->aliases['nid']}])) {
         $ids[$result->{$this->aliases['nid']}] = array();
@@ -129,7 +129,7 @@ public function preRender(&$values) {
       ));
       foreach ($result as $node) {
         foreach ($ids[$node->id()] as $id) {
-          $values[$id]->{$this->field_alias} = $node->num_comments;
+          $values[$id]->{$this->fieldAlias} = $node->num_comments;
         }
       }
     }
diff --git a/core/modules/comment/src/Plugin/views/field/StatisticsLastCommentName.php b/core/modules/comment/src/Plugin/views/field/StatisticsLastCommentName.php
index cdd6988..516fae6 100644
--- a/core/modules/comment/src/Plugin/views/field/StatisticsLastCommentName.php
+++ b/core/modules/comment/src/Plugin/views/field/StatisticsLastCommentName.php
@@ -42,7 +42,7 @@ public function query() {
     // nes_user alias so this can work with the sort handler, below.
     $this->user_table = $this->query->ensureTable('ces_users', $this->relationship, $join);
 
-    $this->field_alias = $this->query->addField(NULL, "COALESCE($this->user_table.name, $this->tableAlias.$this->field)", $this->tableAlias . '_' . $this->field);
+    $this->fieldAlias = $this->query->addField(NULL, "COALESCE($this->user_table.name, $this->tableAlias.$this->field)", $this->tableAlias . '_' . $this->field);
 
     $this->user_field = $this->query->addField($this->user_table, 'name');
     $this->uid = $this->query->addField($this->tableAlias, 'last_comment_uid');
diff --git a/core/modules/comment/src/Plugin/views/field/StatisticsLastUpdated.php b/core/modules/comment/src/Plugin/views/field/StatisticsLastUpdated.php
index 860d5bd..d48ad06 100644
--- a/core/modules/comment/src/Plugin/views/field/StatisticsLastUpdated.php
+++ b/core/modules/comment/src/Plugin/views/field/StatisticsLastUpdated.php
@@ -21,7 +21,7 @@ class StatisticsLastUpdated extends Date {
   public function query() {
     $this->ensureMyTable();
     $this->node_table = $this->query->ensureTable('node', $this->relationship);
-    $this->field_alias = $this->query->addField(NULL, "GREATEST(" . $this->node_table . ".changed, " . $this->tableAlias . ".last_comment_timestamp)", $this->tableAlias . '_' . $this->field);
+    $this->fieldAlias = $this->query->addField(NULL, "GREATEST(" . $this->node_table . ".changed, " . $this->tableAlias . ".last_comment_timestamp)", $this->tableAlias . '_' . $this->field);
   }
 
 }
diff --git a/core/modules/comment/src/Plugin/views/field/Username.php b/core/modules/comment/src/Plugin/views/field/Username.php
index b526dbc..e1a5f9d 100644
--- a/core/modules/comment/src/Plugin/views/field/Username.php
+++ b/core/modules/comment/src/Plugin/views/field/Username.php
@@ -30,8 +30,8 @@ class Username extends FieldPluginBase {
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields['uid'] = 'uid';
-    $this->additional_fields['homepage'] = 'homepage';
+    $this->additionalFields['uid'] = 'uid';
+    $this->additionalFields['homepage'] = 'homepage';
   }
 
   protected function defineOptions() {
diff --git a/core/modules/dblog/src/Plugin/views/field/DblogMessage.php b/core/modules/dblog/src/Plugin/views/field/DblogMessage.php
index 6c94184..9018d56 100644
--- a/core/modules/dblog/src/Plugin/views/field/DblogMessage.php
+++ b/core/modules/dblog/src/Plugin/views/field/DblogMessage.php
@@ -30,7 +30,7 @@ public function init(ViewExecutable $view, DisplayPluginBase $display, array &$o
     parent::init($view, $display, $options);
 
     if ($this->options['replace_variables']) {
-      $this->additional_fields['variables'] = 'variables';
+      $this->additionalFields['variables'] = 'variables';
     }
   }
 
diff --git a/core/modules/field/src/Plugin/views/field/Field.php b/core/modules/field/src/Plugin/views/field/Field.php
index 4705437..6ac561c 100644
--- a/core/modules/field/src/Plugin/views/field/Field.php
+++ b/core/modules/field/src/Plugin/views/field/Field.php
@@ -254,7 +254,7 @@ public function query($use_groupby = FALSE) {
     $this->get_base_table();
 
     $entity_type = $this->definition['entity_tables'][$this->base_table];
-    $fields = $this->additional_fields;
+    $fields = $this->additionalFields;
     // No need to add the entity type.
     $entity_type_key = array_search('entity_type', $fields);
     if ($entity_type_key !== FALSE) {
diff --git a/core/modules/file/src/Plugin/views/field/File.php b/core/modules/file/src/Plugin/views/field/File.php
index 135ff7f..15d4832 100644
--- a/core/modules/file/src/Plugin/views/field/File.php
+++ b/core/modules/file/src/Plugin/views/field/File.php
@@ -29,7 +29,7 @@ public function init(ViewExecutable $view, DisplayPluginBase $display, array &$o
     parent::init($view, $display, $options);
 
     if (!empty($options['link_to_file'])) {
-      $this->additional_fields['uri'] = 'uri';
+      $this->additionalFields['uri'] = 'uri';
     }
   }
 
diff --git a/core/modules/file/src/Plugin/views/field/FileMime.php b/core/modules/file/src/Plugin/views/field/FileMime.php
index 5576e34..4627f21 100644
--- a/core/modules/file/src/Plugin/views/field/FileMime.php
+++ b/core/modules/file/src/Plugin/views/field/FileMime.php
@@ -38,7 +38,7 @@ public function buildOptionsForm(&$form, FormStateInterface $form_state) {
    * {@inheritdoc}
    */
   public function render(ResultRow $values) {
-    $data = $values->{$this->field_alias};
+    $data = $values->{$this->fieldAlias};
     if (!empty($this->options['filemime_image']) && $data !== NULL && $data !== '') {
       $file_icon = array(
         '#theme' => 'image__file_icon',
diff --git a/core/modules/file/src/Plugin/views/field/Uri.php b/core/modules/file/src/Plugin/views/field/Uri.php
index 2d2c481..2591c34 100644
--- a/core/modules/file/src/Plugin/views/field/Uri.php
+++ b/core/modules/file/src/Plugin/views/field/Uri.php
@@ -37,7 +37,7 @@ public function buildOptionsForm(&$form, FormStateInterface $form_state) {
    * {@inheritdoc}
    */
   public function render(ResultRow $values) {
-    $data = $values->{$this->field_alias};
+    $data = $values->{$this->fieldAlias};
     if (!empty($this->options['file_download_path']) && $data !== NULL && $data !== '') {
       $data = file_create_url($data);
     }
diff --git a/core/modules/history/src/Plugin/views/field/HistoryUserTimestamp.php b/core/modules/history/src/Plugin/views/field/HistoryUserTimestamp.php
index 4a7d0c1..45372ea 100644
--- a/core/modules/history/src/Plugin/views/field/HistoryUserTimestamp.php
+++ b/core/modules/history/src/Plugin/views/field/HistoryUserTimestamp.php
@@ -39,10 +39,10 @@ public function init(ViewExecutable $view, DisplayPluginBase $display, array &$o
     parent::init($view, $display, $options);
 
     if (\Drupal::currentUser()->isAuthenticated()) {
-      $this->additional_fields['created'] = array('table' => 'node_field_data', 'field' => 'created');
-      $this->additional_fields['changed'] = array('table' => 'node_field_data', 'field' => 'changed');
+      $this->additionalFields['created'] = array('table' => 'node_field_data', 'field' => 'created');
+      $this->additionalFields['changed'] = array('table' => 'node_field_data', 'field' => 'changed');
       if (\Drupal::moduleHandler()->moduleExists('comment') && !empty($this->options['comments'])) {
-        $this->additional_fields['last_comment'] = array('table' => 'comment_entity_statistics', 'field' => 'last_comment_timestamp');
+        $this->additionalFields['last_comment'] = array('table' => 'comment_entity_statistics', 'field' => 'last_comment_timestamp');
       }
     }
   }
diff --git a/core/modules/node/src/Plugin/views/field/Node.php b/core/modules/node/src/Plugin/views/field/Node.php
index ae74239..fe81812 100644
--- a/core/modules/node/src/Plugin/views/field/Node.php
+++ b/core/modules/node/src/Plugin/views/field/Node.php
@@ -32,7 +32,7 @@ public function init(ViewExecutable $view, DisplayPluginBase $display, array &$o
 
     // Don't add the additional fields to groupby
     if (!empty($this->options['link_to_node'])) {
-      $this->additional_fields['nid'] = array('table' => 'node', 'field' => 'nid');
+      $this->additionalFields['nid'] = array('table' => 'node', 'field' => 'nid');
     }
   }
 
@@ -68,7 +68,7 @@ public function buildOptionsForm(&$form, FormStateInterface $form_state) {
    *   Returns a string for the link text.
    */
   protected function renderLink($data, ResultRow $values) {
-    if (!empty($this->options['link_to_node']) && !empty($this->additional_fields['nid'])) {
+    if (!empty($this->options['link_to_node']) && !empty($this->additionalFields['nid'])) {
       if ($data !== NULL && $data !== '') {
         $this->options['alter']['make_link'] = TRUE;
         $this->options['alter']['path'] = "node/" . $this->getValue($values, 'nid');
diff --git a/core/modules/node/src/Plugin/views/field/Path.php b/core/modules/node/src/Plugin/views/field/Path.php
index 53b5010..2371355 100644
--- a/core/modules/node/src/Plugin/views/field/Path.php
+++ b/core/modules/node/src/Plugin/views/field/Path.php
@@ -28,7 +28,7 @@ class Path extends FieldPluginBase {
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields['nid'] = 'nid';
+    $this->additionalFields['nid'] = 'nid';
   }
 
   protected function defineOptions() {
diff --git a/core/modules/node/src/Plugin/views/field/Revision.php b/core/modules/node/src/Plugin/views/field/Revision.php
index 040c63f..4207dbb 100644
--- a/core/modules/node/src/Plugin/views/field/Revision.php
+++ b/core/modules/node/src/Plugin/views/field/Revision.php
@@ -29,8 +29,8 @@ public function init(ViewExecutable $view, DisplayPluginBase $display, array &$o
     parent::init($view, $display, $options);
 
     if (!empty($this->options['link_to_node_revision'])) {
-      $this->additional_fields['vid'] = 'vid';
-      $this->additional_fields['nid'] = 'nid';
+      $this->additionalFields['vid'] = 'vid';
+      $this->additionalFields['nid'] = 'nid';
     }
   }
   protected function defineOptions() {
diff --git a/core/modules/node/src/Plugin/views/field/RevisionLink.php b/core/modules/node/src/Plugin/views/field/RevisionLink.php
index 5ea0835..119d77b 100644
--- a/core/modules/node/src/Plugin/views/field/RevisionLink.php
+++ b/core/modules/node/src/Plugin/views/field/RevisionLink.php
@@ -28,7 +28,7 @@ class RevisionLink extends Link {
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields['node_vid'] = array('table' => 'node_revision', 'field' => 'vid');
+    $this->additionalFields['node_vid'] = array('table' => 'node_revision', 'field' => 'vid');
   }
 
   /**
diff --git a/core/modules/rest/src/Plugin/views/row/DataFieldRow.php b/core/modules/rest/src/Plugin/views/row/DataFieldRow.php
index 821ed48..b8ea434 100644
--- a/core/modules/rest/src/Plugin/views/row/DataFieldRow.php
+++ b/core/modules/rest/src/Plugin/views/row/DataFieldRow.php
@@ -141,7 +141,7 @@ public function render($row) {
     foreach ($this->view->field as $id => $field) {
       // If this is not unknown and the raw output option has been set, just get
       // the raw value.
-      if (($field->field_alias != 'unknown') && !empty($this->rawOutputOptions[$id])) {
+      if (($field->fieldAlias != 'unknown') && !empty($this->rawOutputOptions[$id])) {
         $value = $field->sanitizeValue($field->getValue($row), 'xss_admin');
       }
       // Otherwise, pass this through the field advancedRender() method.
diff --git a/core/modules/search/src/Plugin/views/field/Score.php b/core/modules/search/src/Plugin/views/field/Score.php
index bb5c3fe..7307c1a 100644
--- a/core/modules/search/src/Plugin/views/field/Score.php
+++ b/core/modules/search/src/Plugin/views/field/Score.php
@@ -29,7 +29,7 @@ public function query() {
     // one or obviously this won't work.
     foreach ($this->view->filter as $handler) {
       if (isset($handler->search_score) && ($handler->relationship == $this->relationship)) {
-        $this->field_alias = $handler->search_score;
+        $this->fieldAlias = $handler->search_score;
         $this->tableAlias = $handler->tableAlias;
         return;
       }
diff --git a/core/modules/taxonomy/src/Plugin/views/field/LinkEdit.php b/core/modules/taxonomy/src/Plugin/views/field/LinkEdit.php
index a0b1e67..9e92f07 100644
--- a/core/modules/taxonomy/src/Plugin/views/field/LinkEdit.php
+++ b/core/modules/taxonomy/src/Plugin/views/field/LinkEdit.php
@@ -28,8 +28,8 @@ class LinkEdit extends FieldPluginBase {
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields['tid'] = 'tid';
-    $this->additional_fields['vid'] = 'vid';
+    $this->additionalFields['tid'] = 'tid';
+    $this->additionalFields['vid'] = 'vid';
   }
 
   protected function defineOptions() {
diff --git a/core/modules/taxonomy/src/Plugin/views/field/Taxonomy.php b/core/modules/taxonomy/src/Plugin/views/field/Taxonomy.php
index 2a7dd73..f9ed185 100644
--- a/core/modules/taxonomy/src/Plugin/views/field/Taxonomy.php
+++ b/core/modules/taxonomy/src/Plugin/views/field/Taxonomy.php
@@ -35,8 +35,8 @@ class Taxonomy extends FieldPluginBase {
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields['vid'] = 'vid';
-    $this->additional_fields['tid'] = 'tid';
+    $this->additionalFields['vid'] = 'vid';
+    $this->additionalFields['tid'] = 'tid';
   }
 
   protected function defineOptions() {
diff --git a/core/modules/taxonomy/src/Plugin/views/field/TaxonomyIndexTid.php b/core/modules/taxonomy/src/Plugin/views/field/TaxonomyIndexTid.php
index 2bae2fe..1065a37 100644
--- a/core/modules/taxonomy/src/Plugin/views/field/TaxonomyIndexTid.php
+++ b/core/modules/taxonomy/src/Plugin/views/field/TaxonomyIndexTid.php
@@ -30,10 +30,10 @@ public function init(ViewExecutable $view, DisplayPluginBase $display, array &$o
 
     // @todo: Wouldn't it be possible to use $this->base_table and no if here?
     if ($view->storage->get('base_table') == 'node_field_revision') {
-      $this->additional_fields['nid'] = array('table' => 'node_field_revision', 'field' => 'nid');
+      $this->additionalFields['nid'] = array('table' => 'node_field_revision', 'field' => 'nid');
     }
     else {
-      $this->additional_fields['nid'] = array('table' => 'node', 'field' => 'nid');
+      $this->additionalFields['nid'] = array('table' => 'node', 'field' => 'nid');
     }
   }
 
@@ -94,7 +94,7 @@ public function query() {
 
   public function preRender(&$values) {
     $vocabularies = entity_load_multiple('taxonomy_vocabulary');
-    $this->field_alias = $this->aliases['nid'];
+    $this->fieldAlias = $this->aliases['nid'];
     $nids = array();
     foreach ($values as $result) {
       if (!empty($result->{$this->aliases['nid']})) {
diff --git a/core/modules/user/src/Plugin/views/field/Link.php b/core/modules/user/src/Plugin/views/field/Link.php
index 40ff364..31c93a0 100644
--- a/core/modules/user/src/Plugin/views/field/Link.php
+++ b/core/modules/user/src/Plugin/views/field/Link.php
@@ -37,7 +37,7 @@ public function usesGroupBy() {
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields['uid'] = 'uid';
+    $this->additionalFields['uid'] = 'uid';
   }
 
   protected function defineOptions() {
diff --git a/core/modules/user/src/Plugin/views/field/Name.php b/core/modules/user/src/Plugin/views/field/Name.php
index 5396bc6..1f749e1 100644
--- a/core/modules/user/src/Plugin/views/field/Name.php
+++ b/core/modules/user/src/Plugin/views/field/Name.php
@@ -32,7 +32,7 @@ public function init(ViewExecutable $view, DisplayPluginBase $display, array &$o
     parent::init($view, $display, $options);
 
     if (!empty($this->options['overwrite_anonymous']) || !empty($this->options['format_username'])) {
-      $this->additional_fields['uid'] = 'uid';
+      $this->additionalFields['uid'] = 'uid';
     }
   }
 
diff --git a/core/modules/user/src/Plugin/views/field/Permissions.php b/core/modules/user/src/Plugin/views/field/Permissions.php
index 92d7171..bc1d9fd 100644
--- a/core/modules/user/src/Plugin/views/field/Permissions.php
+++ b/core/modules/user/src/Plugin/views/field/Permissions.php
@@ -71,12 +71,12 @@ public static function create(ContainerInterface $container, array $configuratio
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields['uid'] = array('table' => 'users', 'field' => 'uid');
+    $this->additionalFields['uid'] = array('table' => 'users', 'field' => 'uid');
   }
 
   public function query() {
     $this->addAdditionalFields();
-    $this->field_alias = $this->aliases['uid'];
+    $this->fieldAlias = $this->aliases['uid'];
   }
 
   public function preRender(&$values) {
diff --git a/core/modules/user/src/Plugin/views/field/Roles.php b/core/modules/user/src/Plugin/views/field/Roles.php
index 57506a8..5e209c0 100644
--- a/core/modules/user/src/Plugin/views/field/Roles.php
+++ b/core/modules/user/src/Plugin/views/field/Roles.php
@@ -61,12 +61,12 @@ public static function create(ContainerInterface $container, array $configuratio
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields['uid'] = array('table' => 'users', 'field' => 'uid');
+    $this->additionalFields['uid'] = array('table' => 'users', 'field' => 'uid');
   }
 
   public function query() {
     $this->addAdditionalFields();
-    $this->field_alias = $this->aliases['uid'];
+    $this->fieldAlias = $this->aliases['uid'];
   }
 
   public function preRender(&$values) {
diff --git a/core/modules/user/src/Plugin/views/field/User.php b/core/modules/user/src/Plugin/views/field/User.php
index d49c7e1..6dd8aa6 100644
--- a/core/modules/user/src/Plugin/views/field/User.php
+++ b/core/modules/user/src/Plugin/views/field/User.php
@@ -29,7 +29,7 @@ public function init(ViewExecutable $view, DisplayPluginBase $display, array &$o
     parent::init($view, $display, $options);
 
     if (!empty($this->options['link_to_user'])) {
-      $this->additional_fields['uid'] = 'uid';
+      $this->additionalFields['uid'] = 'uid';
     }
   }
 
diff --git a/core/modules/views/src/Plugin/views/field/EntityLabel.php b/core/modules/views/src/Plugin/views/field/EntityLabel.php
index 376c497..b4eac11 100644
--- a/core/modules/views/src/Plugin/views/field/EntityLabel.php
+++ b/core/modules/views/src/Plugin/views/field/EntityLabel.php
@@ -71,7 +71,7 @@ public static function create(ContainerInterface $container, array $configuratio
    */
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
-    $this->additional_fields[$this->definition['entity type field']] = $this->definition['entity type field'];
+    $this->additionalFields[$this->definition['entity type field']] = $this->definition['entity type field'];
   }
 
   /**
diff --git a/core/modules/views/src/Plugin/views/field/FieldPluginBase.php b/core/modules/views/src/Plugin/views/field/FieldPluginBase.php
index d4e04f9..6aad5ae 100644
--- a/core/modules/views/src/Plugin/views/field/FieldPluginBase.php
+++ b/core/modules/views/src/Plugin/views/field/FieldPluginBase.php
@@ -69,22 +69,33 @@
    */
   const RENDER_TEXT_PHASE_EMPTY = 2;
 
-  var $field_alias = 'unknown';
-  var $aliases = array();
+  /**
+   * The alias that results from adding a field to a query.
+   *
+   * @var string
+   */
+  public $fieldAlias = 'unknown';
+
+  /**
+   * The generated aliases.
+   *
+   * @var array
+   */
+  public $aliases = array();
 
   /**
    * The field value prior to any rewriting.
    *
    * @var mixed
    */
-  public $original_value = NULL;
+  public $originalValue = NULL;
 
   /**
    * @var array
-   * Stores additional fields which get's added to the query.
+   * Stores additional fields which get added to the query.
    * The generated aliases are stored in $aliases.
    */
-  var $additional_fields = array();
+  public $additionalFields = array();
 
   /**
    * Overrides Drupal\views\Plugin\views\HandlerBase::init().
@@ -92,9 +103,9 @@
   public function init(ViewExecutable $view, DisplayPluginBase $display, array &$options = NULL) {
     parent::init($view, $display, $options);
 
-    $this->additional_fields = array();
+    $this->additionalFields = array();
     if (!empty($this->definition['additional fields'])) {
-      $this->additional_fields = $this->definition['additional fields'];
+      $this->additionalFields = $this->definition['additional fields'];
     }
 
     if (!isset($this->options['exclude'])) {
@@ -119,7 +130,7 @@ public function query() {
     $this->ensureMyTable();
     // Add the field.
     $params = $this->options['group_type'] != 'group' ? array('function' => $this->options['group_type']) : array();
-    $this->field_alias = $this->query->addField($this->tableAlias, $this->realField, NULL, $params);
+    $this->fieldAlias = $this->query->addField($this->tableAlias, $this->realField, NULL, $params);
 
     $this->addAdditionalFields();
   }
@@ -137,10 +148,10 @@ public function query() {
   protected function addAdditionalFields($fields = NULL) {
     if (!isset($fields)) {
       // notice check
-      if (empty($this->additional_fields)) {
+      if (empty($this->additionalFields)) {
         return;
       }
-      $fields = $this->additional_fields;
+      $fields = $this->additionalFields;
     }
 
     $group_params = array();
@@ -185,11 +196,11 @@ protected function addAdditionalFields($fields = NULL) {
    * Called to determine what to tell the clicksorter.
    */
   public function clickSort($order) {
-    if (isset($this->field_alias)) {
+    if (isset($this->fieldAlias)) {
       // Since fields should always have themselves already added, just
       // add a sort on the field.
       $params = $this->options['group_type'] != 'group' ? array('function' => $this->options['group_type']) : array();
-      $this->query->addOrderBy(NULL, NULL, $order, $this->field_alias, $params);
+      $this->query->addOrderBy(NULL, NULL, $order, $this->fieldAlias, $params);
     }
   }
 
@@ -408,7 +419,7 @@ public function getEntity(ResultRow $values) {
    *   Optional name of the field where the value is stored.
    */
   public function getValue(ResultRow $values, $field = NULL) {
-    $alias = isset($field) ? $this->aliases[$field] : $this->field_alias;
+    $alias = isset($field) ? $this->aliases[$field] : $this->fieldAlias;
     if (isset($values->{$alias})) {
       return $values->{$alias};
     }
@@ -1133,7 +1144,7 @@ public function advancedRender(ResultRow $values) {
       $raw_items = $this->getItems($values);
       // If there are no items, set the original value to NULL.
       if (empty($raw_items)) {
-        $this->original_value = NULL;
+        $this->originalValue = NULL;
       }
     }
     else {
@@ -1142,7 +1153,7 @@ public function advancedRender(ResultRow $values) {
         $value = drupal_render($value);
       }
       $this->last_render = $value;
-      $this->original_value = $value;
+      $this->originalValue = $value;
     }
 
     if ($this->allowAdvancedRender()) {
@@ -1155,7 +1166,7 @@ public function advancedRender(ResultRow $values) {
             $value = drupal_render($value);
           }
           $this->last_render = $value;
-          $this->original_value = $this->last_render;
+          $this->originalValue = $this->last_render;
 
           $alter = $item + $this->options['alter'];
           $alter['phase'] = static::RENDER_TEXT_PHASE_SINGLE_ITEM;
@@ -1239,7 +1250,7 @@ public function renderText($alter) {
     }
 
     // Check if there should be no further rewrite for empty values.
-    $no_rewrite_for_empty = $this->options['hide_alter_empty'] && $this->isValueEmpty($this->original_value, $this->options['empty_zero']);
+    $no_rewrite_for_empty = $this->options['hide_alter_empty'] && $this->isValueEmpty($this->originalValue, $this->options['empty_zero']);
 
     // Check whether the value is empty and return nothing, so the field isn't rendered.
     // First check whether the field should be hidden if the value(hide_alter_empty = TRUE) /the rewrite is empty (hide_alter_empty = FALSE).
diff --git a/core/modules/views/src/Plugin/views/field/MachineName.php b/core/modules/views/src/Plugin/views/field/MachineName.php
index 4b3521b..a7a2d96 100644
--- a/core/modules/views/src/Plugin/views/field/MachineName.php
+++ b/core/modules/views/src/Plugin/views/field/MachineName.php
@@ -72,7 +72,7 @@ public function preRender(&$values) {
    * {@inheritdoc}
    */
   public function render(ResultRow $values) {
-    $value = $values->{$this->field_alias};
+    $value = $values->{$this->fieldAlias};
     if (!empty($this->options['machine_name']) || !isset($this->valueOptions[$value])) {
       $result = String::checkPlain($value);
     }
diff --git a/core/modules/views/src/Plugin/views/field/Markup.php b/core/modules/views/src/Plugin/views/field/Markup.php
index 465f655..877b2ea 100644
--- a/core/modules/views/src/Plugin/views/field/Markup.php
+++ b/core/modules/views/src/Plugin/views/field/Markup.php
@@ -34,9 +34,9 @@ public function init(ViewExecutable $view, DisplayPluginBase $display, array &$o
 
     $this->format = $this->definition['format'];
 
-    $this->additional_fields = array();
+    $this->additionalFields = array();
     if (is_array($this->format)) {
-      $this->additional_fields['format'] = $this->format;
+      $this->additionalFields['format'] = $this->format;
     }
   }
 
diff --git a/core/modules/views/src/Plugin/views/field/Serialized.php b/core/modules/views/src/Plugin/views/field/Serialized.php
index c9d0dd2..8065705 100644
--- a/core/modules/views/src/Plugin/views/field/Serialized.php
+++ b/core/modules/views/src/Plugin/views/field/Serialized.php
@@ -65,7 +65,7 @@ public function validateOptionsForm(&$form, FormStateInterface $form_state) {
    * {@inheritdoc}
    */
   public function render(ResultRow $values) {
-    $value = $values->{$this->field_alias};
+    $value = $values->{$this->fieldAlias};
 
     if ($this->options['format'] == 'unserialized') {
       return String::checkPlain(print_r(unserialize($value), TRUE));
diff --git a/core/modules/views/src/Plugin/views/field/TimeInterval.php b/core/modules/views/src/Plugin/views/field/TimeInterval.php
index 62f0286..53bb00d 100644
--- a/core/modules/views/src/Plugin/views/field/TimeInterval.php
+++ b/core/modules/views/src/Plugin/views/field/TimeInterval.php
@@ -80,7 +80,7 @@ public function buildOptionsForm(&$form, FormStateInterface $form_state) {
    * {@inheritdoc}
    */
   public function render(ResultRow $values) {
-    $value = $values->{$this->field_alias};
+    $value = $values->{$this->fieldAlias};
     return $this->dateFormatter->formatInterval($value, isset($this->options['granularity']) ? $this->options['granularity'] : 2);
   }
 
diff --git a/core/modules/views/src/Plugin/views/filter/Combine.php b/core/modules/views/src/Plugin/views/filter/Combine.php
index 12e6f22..0871748 100644
--- a/core/modules/views/src/Plugin/views/filter/Combine.php
+++ b/core/modules/views/src/Plugin/views/filter/Combine.php
@@ -64,7 +64,7 @@ public function query() {
       $field = $this->view->field[$id];
       // Always add the table of the selected fields to be sure a table alias exists.
       $field->ensureMyTable();
-      if (!empty($field->field_alias) && !empty($field->field_alias)) {
+      if (!empty($field->fieldAlias) && !empty($field->fieldAlias)) {
         $fields[] = "$field->tableAlias.$field->realField";
       }
     }
diff --git a/core/modules/views/src/Plugin/views/row/OpmlFields.php b/core/modules/views/src/Plugin/views/row/OpmlFields.php
index 2e936f5..4eab681 100644
--- a/core/modules/views/src/Plugin/views/row/OpmlFields.php
+++ b/core/modules/views/src/Plugin/views/row/OpmlFields.php
@@ -200,7 +200,7 @@ public function render($row) {
       '#view' => $this->view,
       '#options' => $this->options,
       '#row' => $item,
-      '#field_alias' => isset($this->field_alias) ? $this->field_alias : '',
+      '#fieldAlias' => isset($this->field_alias) ? $this->field_alias : '',
     );
     return $build;
   }
diff --git a/core/modules/views/src/Plugin/views/row/RowPluginBase.php b/core/modules/views/src/Plugin/views/row/RowPluginBase.php
index 905f04e..7942760 100644
--- a/core/modules/views/src/Plugin/views/row/RowPluginBase.php
+++ b/core/modules/views/src/Plugin/views/row/RowPluginBase.php
@@ -175,7 +175,7 @@ public function render($row) {
       '#view' => $this->view,
       '#options' => $this->options,
       '#row' => $row,
-      '#field_alias' => isset($this->field_alias) ? $this->field_alias : '',
+      '#fieldAlias' => isset($this->field_alias) ? $this->field_alias : '',
     );
   }
 
diff --git a/core/modules/views/src/Plugin/views/row/RssFields.php b/core/modules/views/src/Plugin/views/row/RssFields.php
index 48dcefe..a840432 100644
--- a/core/modules/views/src/Plugin/views/row/RssFields.php
+++ b/core/modules/views/src/Plugin/views/row/RssFields.php
@@ -178,7 +178,7 @@ public function render($row) {
       '#view' => $this->view,
       '#options' => $this->options,
       '#row' => $item,
-      '#field_alias' => isset($this->field_alias) ? $this->field_alias : '',
+      '#fieldAlias' => isset($this->field_alias) ? $this->field_alias : '',
     );
     return drupal_render($build);
   }
diff --git a/core/modules/views/src/Tests/Handler/FieldUnitTest.php b/core/modules/views/src/Tests/Handler/FieldUnitTest.php
index 12fe74e..f49fcbf 100644
--- a/core/modules/views/src/Tests/Handler/FieldUnitTest.php
+++ b/core/modules/views/src/Tests/Handler/FieldUnitTest.php
@@ -64,9 +64,9 @@ public function testQuery() {
     $view->initHandlers();
 
     $id_field = $view->field['id'];
-    $id_field->additional_fields['job'] = 'job';
+    $id_field->additionalFields['job'] = 'job';
     // Choose also a field alias key which doesn't match to the table field.
-    $id_field->additional_fields['created_test'] = array('table' => 'views_test_data', 'field' => 'created');
+    $id_field->additionalFields['created_test'] = array('table' => 'views_test_data', 'field' => 'created');
     $view->build();
 
     // Make sure the field aliases have the expected value.
diff --git a/core/modules/views/templates/views-view-field.html.twig b/core/modules/views/templates/views-view-field.html.twig
index a058548..91bd468 100644
--- a/core/modules/views/templates/views-view-field.html.twig
+++ b/core/modules/views/templates/views-view-field.html.twig
@@ -14,7 +14,7 @@
  * - output: The processed output that will normally be used.
  *
  * When fetching output from the row this construct should be used:
- * data = row[field.field_alias]
+ * data = row[field.fieldAlias]
  *
  * The above will guarantee that you'll always get the correct data, regardless
  * of any changes in the aliasing that might happen if the view is modified.
diff --git a/core/modules/views/views.module b/core/modules/views/views.module
index 3294836..19d3bb1 100644
--- a/core/modules/views/views.module
+++ b/core/modules/views/views.module
@@ -131,7 +131,7 @@ function views_theme($existing, $type, $theme, $path) {
     // attaches contextual links when the primary theme argument is an array.
     'display' => array('view_array' => array(), 'view' => NULL),
     'style' => array('view' => NULL, 'options' => NULL, 'rows' => NULL, 'title' => NULL),
-    'row' => array('view' => NULL, 'options' => NULL, 'row' => NULL, 'field_alias' => NULL),
+    'row' => array('view' => NULL, 'options' => NULL, 'row' => NULL, 'fieldAlias' => NULL),
     'exposed_form' => array('view' => NULL, 'options' => NULL),
     'pager' => array(
       'view' => NULL, 'options' => NULL,
diff --git a/core/modules/views/views.theme.inc b/core/modules/views/views.theme.inc
index 7af7216..4a2f3af 100644
--- a/core/modules/views/views.theme.inc
+++ b/core/modules/views/views.theme.inc
@@ -195,8 +195,8 @@ function template_preprocess_views_view_fields(&$variables) {
       }
 
       $object->content = $field_output;
-      if (isset($view->field[$id]->field_alias) && isset($variables['row']->{$view->field[$id]->field_alias})) {
-        $object->raw = $variables['row']->{$view->field[$id]->field_alias};
+      if (isset($view->field[$id]->fieldAlias) && isset($variables['row']->{$view->field[$id]->fieldAlias})) {
+        $object->raw = $variables['row']->{$view->field[$id]->fieldAlias};
       }
       else {
         $object->raw = NULL; // make sure it exists to reduce NOTICE
@@ -329,8 +329,8 @@ function template_preprocess_views_view_grouping(&$variables) {
  * Display a single views field.
  *
  * Interesting bits of info:
- * $field->field_alias says what the raw value in $row will be. Reach it like
- * this: @code { $row->{$field->field_alias} @endcode
+ * $field->fieldAlias says what the raw value in $row will be. Reach it like
+ * this: @code { $row->{$field->fieldAlias} @endcode
  */
 function theme_views_view_field($variables) {
   return $variables['output'];