diff --git a/core/lib/Drupal/Core/Entity/ContentEntityDatabaseStorage.php b/core/lib/Drupal/Core/Entity/ContentEntityDatabaseStorage.php
index a650fce..0cfb7c4 100644
--- a/core/lib/Drupal/Core/Entity/ContentEntityDatabaseStorage.php
+++ b/core/lib/Drupal/Core/Entity/ContentEntityDatabaseStorage.php
@@ -1141,8 +1141,7 @@ public function onFieldCreate(FieldStorageDefinitionInterface $storage_definitio
   /**
    * {@inheritdoc}
    */
-  public function onFieldUpdate(FieldStorageDefinitionInterface $storage_definition) {
-    $original = $storage_definition->original;
+  public function onFieldUpdate(FieldStorageDefinitionInterface $storage_definition, FieldStorageDefinitionInterface $original) {
 
     if (!$storage_definition->hasData()) {
       // There is no data. Re-create the tables completely.
@@ -1252,11 +1251,11 @@ public function onInstanceDelete(FieldDefinitionInterface $field_definition) {
     $revision_name = static::_fieldRevisionTableName($field_definition);
     $this->database->update($table_name)
       ->fields(array('deleted' => 1))
-      ->condition('bundle', $field_definition->bundle)
+      ->condition('bundle', $field_definition->getBundle())
       ->execute();
     $this->database->update($revision_name)
       ->fields(array('deleted' => 1))
-      ->condition('bundle', $field_definition->bundle)
+      ->condition('bundle', $field_definition->getBundle())
       ->execute();
   }
 
@@ -1292,7 +1291,7 @@ protected function readFieldItemsToPurge(FieldDefinitionInterface $field_definit
     $table_name = static::_fieldTableName($field_definition, $is_deleted);
     $query = $this->database->select($table_name, 't', array('fetch' => \PDO::FETCH_ASSOC))
       ->fields('t')
-      ->condition('bundle', $field_definition->bundle)
+      ->condition('bundle', $field_definition->getBundle())
       ->orderBy('entity_id')
       ->orderBy('revision_id')
       ->orderBy('delta')
@@ -1396,17 +1395,8 @@ public function countFieldData($storage_definition, $as_bool = FALSE) {
    * @see hook_schema()
    */
   public static function _fieldSqlSchema(FieldStorageDefinitionInterface $storage_definition, array $schema = NULL, $deleted = FALSE) {
-    if ($storage_definition->deleted && !$deleted) {
-      throw new \Exception("Field schema for deleted field to be returned.");
-    }
-    if ($deleted) {
-      $description_current = "Data storage for deleted field {$storage_definition->getUniqueStorageIdentifier()} ({$storage_definition->getTargetEntityTypeId()}, {$storage_definition->getName()}).";
-      $description_revision = "Revision archive storage for deleted field {$storage_definition->getUniqueStorageIdentifier()} ({$storage_definition->getTargetEntityTypeId()}, {$storage_definition->getName()}).";
-    }
-    else {
-      $description_current = "Data storage for {$storage_definition->getTargetEntityTypeId()} field {$storage_definition->getName()}.";
-      $description_revision = "Revision archive storage for {$storage_definition->getTargetEntityTypeId()} field {$storage_definition->getName()}.";
-    }
+    $description_current = "Data storage for {$storage_definition->getTargetEntityTypeId()} field {$storage_definition->getName()}.";
+    $description_revision = "Revision archive storage for {$storage_definition->getTargetEntityTypeId()} field {$storage_definition->getName()}.";
 
     $entity_type_id = $storage_definition->getTargetEntityTypeId();
     $entity_manager = \Drupal::entityManager();
diff --git a/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php b/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php
index 23e1ffa..c72f7de 100644
--- a/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php
+++ b/core/lib/Drupal/Core/Entity/ContentEntityStorageBase.php
@@ -273,7 +273,7 @@ public function onFieldCreate(FieldStorageDefinitionInterface $storage_definitio
   /**
    * {@inheritdoc}
    */
-  public function onFieldUpdate(FieldStorageDefinitionInterface $storage_definition) { }
+  public function onFieldUpdate(FieldStorageDefinitionInterface $storage_definition, FieldStorageDefinitionInterface $original) { }
 
   /**
    * {@inheritdoc}
diff --git a/core/lib/Drupal/Core/Entity/EntityManager.php b/core/lib/Drupal/Core/Entity/EntityManager.php
index 93e9fcf..f27c8d4 100644
--- a/core/lib/Drupal/Core/Entity/EntityManager.php
+++ b/core/lib/Drupal/Core/Entity/EntityManager.php
@@ -391,6 +391,7 @@ protected function buildBaseFieldDefinitions($entity_type_id) {
       if ($base_field_definition instanceof FieldDefinition) {
         $base_field_definition->setName($field_name);
         $base_field_definition->setTargetEntityTypeId($entity_type_id);
+        $base_field_definition->setBundle(NULL);
       }
     }
 
@@ -488,6 +489,7 @@ protected function buildBundleFieldDefinitions($entity_type_id, $bundle, array $
       if ($field_definition instanceof FieldDefinition) {
         $field_definition->setName($field_name);
         $field_definition->setTargetEntityTypeId($entity_type_id);
+        $field_definition->setBundle($bundle);
       }
     }
 
diff --git a/core/lib/Drupal/Core/Entity/FieldableEntityStorageInterface.php b/core/lib/Drupal/Core/Entity/FieldableEntityStorageInterface.php
index 5245d8f..4e27be2 100644
--- a/core/lib/Drupal/Core/Entity/FieldableEntityStorageInterface.php
+++ b/core/lib/Drupal/Core/Entity/FieldableEntityStorageInterface.php
@@ -25,8 +25,10 @@ public function onFieldCreate(FieldStorageDefinitionInterface $storage_definitio
    *
    * @param \Drupal\Core\Field\FieldStorageDefinitionInterface $storage_definition
    *   The field being updated.
+   * @param \Drupal\Core\Field\FieldStorageDefinitionInterface $original
+   *   The original storage definition; i.e., the definition before the update.
    */
-  public function onFieldUpdate(FieldStorageDefinitionInterface $storage_definition);
+  public function onFieldUpdate(FieldStorageDefinitionInterface $storage_definition, FieldStorageDefinitionInterface $original);
 
   /**
    * Allows reaction to the deletion of a field.
diff --git a/core/lib/Drupal/Core/Field/FieldDefinition.php b/core/lib/Drupal/Core/Field/FieldDefinition.php
index a7837a0..6eadbda 100644
--- a/core/lib/Drupal/Core/Field/FieldDefinition.php
+++ b/core/lib/Drupal/Core/Field/FieldDefinition.php
@@ -460,8 +460,7 @@ public function getTargetEntityTypeId() {
    * @param string $entity_type_id
    *   The name of the target entity type to set.
    *
-   * @return static
-   *   The object itself for chaining.
+   * @return $this
    */
   public function setTargetEntityTypeId($entity_type_id) {
     $this->definition['entity_type'] = $entity_type_id;
@@ -471,6 +470,26 @@ public function setTargetEntityTypeId($entity_type_id) {
   /**
    * {@inheritdoc}
    */
+  public function getBundle() {
+    return isset($this->definition['bundle']) ? $this->definition['bundle'] : NULL;
+  }
+
+  /**
+   * Sets the bundle this field is defined for.
+   *
+   * @param string|null $bundle
+   *   The bundle, or NULL if the field is not bundle-specific.
+   *
+   * @return $this
+   */
+  public function setBundle($bundle) {
+    $this->definition['bundle'] = $bundle;
+    return $this;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
   public function getSchema() {
     if (!isset($this->schema)) {
       // Get the schema from the field item class.
@@ -550,5 +569,4 @@ public function getUniqueStorageIdentifier() {
     return $this->getTargetEntityTypeId() . '-' . $this->getName();
   }
 
-
 }
diff --git a/core/lib/Drupal/Core/Field/FieldDefinitionInterface.php b/core/lib/Drupal/Core/Field/FieldDefinitionInterface.php
index a6c9190..194f77b 100644
--- a/core/lib/Drupal/Core/Field/FieldDefinitionInterface.php
+++ b/core/lib/Drupal/Core/Field/FieldDefinitionInterface.php
@@ -55,6 +55,15 @@
 interface FieldDefinitionInterface extends FieldStorageDefinitionInterface, ListDataDefinitionInterface {
 
   /**
+   * Gets the bundle the field is defined for.
+   *
+   * @return string|null
+   *   The bundle the field is defined for, or NULL if it is base field; i.e.,
+   *   it is not bundle-specific.
+   */
+  public function getBundle();
+
+  /**
    * Returns whether the display for the field can be configured.
    *
    * @param string $display_context
diff --git a/core/lib/Drupal/Core/Field/FieldStorageDefinitionInterface.php b/core/lib/Drupal/Core/Field/FieldStorageDefinitionInterface.php
index b8961dc..6adfb1d 100644
--- a/core/lib/Drupal/Core/Field/FieldStorageDefinitionInterface.php
+++ b/core/lib/Drupal/Core/Field/FieldStorageDefinitionInterface.php
@@ -286,7 +286,8 @@ public function getProvider();
   public function hasCustomStorage();
 
   /**
-   * @todo
+   * Returns a unique identifier for the field.
+   *
    * @return string
    */
   public function getUniqueStorageIdentifier();
diff --git a/core/modules/field/src/Entity/FieldConfig.php b/core/modules/field/src/Entity/FieldConfig.php
index 838488d..66aa577 100644
--- a/core/modules/field/src/Entity/FieldConfig.php
+++ b/core/modules/field/src/Entity/FieldConfig.php
@@ -368,7 +368,7 @@ protected function preSaveUpdated(EntityStorageInterface $storage) {
     // Notify the storage. The controller can reject the definition
     // update as invalid by raising an exception, which stops execution before
     // the definition is written to config.
-    $entity_manager->getStorage($this->entity_type)->onFieldUpdate($this);
+    $entity_manager->getStorage($this->entity_type)->onFieldUpdate($this, $this->original);
   }
 
   /**
@@ -744,7 +744,6 @@ public function getUniqueStorageIdentifier() {
     return $this->uuid();
   }
 
-
   /**
    * Helper to retrieve the field item class.
    */
diff --git a/core/modules/field/src/Entity/FieldInstanceConfig.php b/core/modules/field/src/Entity/FieldInstanceConfig.php
index 2b4ff56..25d511f 100644
--- a/core/modules/field/src/Entity/FieldInstanceConfig.php
+++ b/core/modules/field/src/Entity/FieldInstanceConfig.php
@@ -630,6 +630,13 @@ public function getTargetEntityTypeId() {
   /**
    * {@inheritdoc}
    */
+  public function getBundle() {
+    return $this->bundle;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
   public function isQueryable() {
     return TRUE;
   }