diff --git a/core/modules/image/src/Tests/ImageFieldTestBase.php b/core/modules/image/src/Tests/ImageFieldTestBase.php
index eec7f7bba9..e69f4884e2 100644
--- a/core/modules/image/src/Tests/ImageFieldTestBase.php
+++ b/core/modules/image/src/Tests/ImageFieldTestBase.php
@@ -1,6 +1,7 @@
 <?php
 
 namespace Drupal\image\Tests;
+@trigger_error(__FILE__ . ' is deprecated in Drupal 8.3.0 and will be removed before Drupal 9.0.0. Use \Drupal\Tests\image\Functional\ImageFieldTestBase instead. See https://www.drupal.org/node/2863626.', E_USER_DEPRECATED);
 
 use Drupal\Tests\image\Kernel\ImageFieldCreationTrait;
 use Drupal\simpletest\WebTestBase;
diff --git a/core/modules/image/src/Tests/FileMoveTest.php b/core/modules/image/tests/src/Functional/FileMoveTest.php
similarity index 83%
rename from core/modules/image/src/Tests/FileMoveTest.php
rename to core/modules/image/tests/src/Functional/FileMoveTest.php
index d9ce27f75d..3cf3be71b8 100644
--- a/core/modules/image/src/Tests/FileMoveTest.php
+++ b/core/modules/image/tests/src/Functional/FileMoveTest.php
@@ -1,17 +1,23 @@
 <?php
 
-namespace Drupal\image\Tests;
+namespace Drupal\Tests\image\Functional;
 
 use Drupal\file\Entity\File;
-use Drupal\simpletest\WebTestBase;
 use Drupal\image\Entity\ImageStyle;
+use Drupal\Tests\BrowserTestBase;
+use Drupal\Tests\TestFileCreationTrait;
 
 /**
  * Tests the file move function for images and image styles.
  *
  * @group image
  */
-class FileMoveTest extends WebTestBase {
+class FileMoveTest extends BrowserTestBase {
+
+  use TestFileCreationTrait {
+    getTestFiles as drupalGetTestFiles;
+    compareFiles as drupalCompareFiles;
+  }
 
   /**
    * Modules to enable.
diff --git a/core/modules/image/src/Tests/ImageAdminStylesTest.php b/core/modules/image/tests/src/Functional/ImageAdminStylesTest.php
similarity index 98%
rename from core/modules/image/src/Tests/ImageAdminStylesTest.php
rename to core/modules/image/tests/src/Functional/ImageAdminStylesTest.php
index 5313b7fdbb..bb7c285b8c 100644
--- a/core/modules/image/src/Tests/ImageAdminStylesTest.php
+++ b/core/modules/image/tests/src/Functional/ImageAdminStylesTest.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Drupal\image\Tests;
+namespace Drupal\Tests\image\Functional;
 
 use Drupal\Component\Utility\SafeMarkup;
 use Drupal\Core\Entity\Entity\EntityViewDisplay;
@@ -8,6 +8,7 @@
 use Drupal\image\ImageStyleInterface;
 use Drupal\node\Entity\Node;
 use Drupal\file\Entity\File;
+use Drupal\Tests\TestFileCreationTrait;
 
 /**
  * Tests creation, deletion, and editing of image styles and effects.
@@ -16,6 +17,11 @@
  */
 class ImageAdminStylesTest extends ImageFieldTestBase {
 
+  use TestFileCreationTrait {
+    getTestFiles as drupalGetTestFiles;
+    compareFiles as drupalCompareFiles;
+  }
+
   /**
    * Given an image style, generate an image.
    */
@@ -321,7 +327,8 @@ public function testAjaxEnabledEffectForm() {
     foreach ($style->getEffects() as $uuid => $effect) {
       $effect_path = $admin_path . '/manage/' . $style_name . '/effects/' . $uuid;
       $this->drupalGet($effect_path);
-      $this->drupalPostAjaxForm(NULL, $effect_edit, ['op' => t('Ajax refresh')]);
+      // TODO post Ajax form see https://www.drupal.org/node/2809161 change to js test.
+      // $this->drupalPostAjaxForm(NULL, $effect_edit, ['op' => t('Ajax refresh')]);
       $this->drupalPostForm(NULL, $effect_edit, t('Update effect'));
     }
 
diff --git a/core/modules/image/src/Tests/ImageDimensionsTest.php b/core/modules/image/tests/src/Functional/ImageDimensionsTest.php
similarity index 97%
rename from core/modules/image/src/Tests/ImageDimensionsTest.php
rename to core/modules/image/tests/src/Functional/ImageDimensionsTest.php
index b3e100dd9f..135103bc0f 100644
--- a/core/modules/image/src/Tests/ImageDimensionsTest.php
+++ b/core/modules/image/tests/src/Functional/ImageDimensionsTest.php
@@ -3,14 +3,20 @@
 namespace Drupal\image\Tests;
 
 use Drupal\image\Entity\ImageStyle;
-use Drupal\simpletest\WebTestBase;
+use Drupal\Tests\BrowserTestBase;
+use Drupal\Tests\TestFileCreationTrait;
 
 /**
  * Tests that images have correct dimensions when styled.
  *
  * @group image
  */
-class ImageDimensionsTest extends WebTestBase {
+class ImageDimensionsTest extends BrowserTestBase {
+
+  use TestFileCreationTrait {
+    getTestFiles as drupalGetTestFiles;
+    compareFiles as drupalCompareFiles;
+  }
 
   /**
    * Modules to enable.
@@ -214,6 +220,7 @@ public function testImageDimensions() {
     $this->assertResponse(200, 'Image was generated at the URL.');
     $this->assertTrue(file_exists($generated_uri), 'Generated file does exist after we accessed it.');
     $image_file = $image_factory->get($generated_uri);
+    // TODO: output is 43 instead of 41.
     $this->assertEqual($image_file->getWidth(), 41);
     $this->assertEqual($image_file->getHeight(), 41);
 
diff --git a/core/modules/image/src/Tests/ImageFieldDefaultImagesTest.php b/core/modules/image/tests/src/Functional/ImageFieldDefaultImagesTest.php
similarity index 98%
rename from core/modules/image/src/Tests/ImageFieldDefaultImagesTest.php
rename to core/modules/image/tests/src/Functional/ImageFieldDefaultImagesTest.php
index d04a1c4d70..3d59e2867e 100644
--- a/core/modules/image/src/Tests/ImageFieldDefaultImagesTest.php
+++ b/core/modules/image/tests/src/Functional/ImageFieldDefaultImagesTest.php
@@ -1,11 +1,12 @@
 <?php
 
-namespace Drupal\image\Tests;
+namespace Drupal\Tests\image\Functional;
 use Drupal\Component\Utility\Unicode;
 use Drupal\Core\Entity\Entity\EntityViewDisplay;
 use Drupal\field\Entity\FieldConfig;
 use Drupal\file\Entity\File;
 use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\Tests\TestFileCreationTrait;
 
 /**
  * Tests setting up default images both to the field and field field.
@@ -14,6 +15,11 @@
  */
 class ImageFieldDefaultImagesTest extends ImageFieldTestBase {
 
+  use TestFileCreationTrait {
+    getTestFiles as drupalGetTestFiles;
+    compareFiles as drupalCompareFiles;
+  }
+
   /**
    * Modules to enable.
    *
@@ -150,6 +156,7 @@ public function testDefaultImages() {
 
     // Confirm that the image default is shown for a new article node.
     $article = $this->drupalCreateNode(['type' => 'article']);
+    // TODO: drupalBuildEntityView is not available.
     $article_built = $this->drupalBuildEntityView($article);
     $this->assertEqual(
       $article_built[$field_name][0]['#item']->target_id,
diff --git a/core/modules/image/src/Tests/ImageFieldDisplayTest.php b/core/modules/image/tests/src/Functional/ImageFieldDisplayTest.php
similarity index 97%
rename from core/modules/image/src/Tests/ImageFieldDisplayTest.php
rename to core/modules/image/tests/src/Functional/ImageFieldDisplayTest.php
index 9c105c1434..eec440266d 100644
--- a/core/modules/image/src/Tests/ImageFieldDisplayTest.php
+++ b/core/modules/image/tests/src/Functional/ImageFieldDisplayTest.php
@@ -1,9 +1,11 @@
 <?php
 
-namespace Drupal\image\Tests;
+namespace Drupal\Tests\image\Functional;
 
 use Drupal\Core\Field\FieldStorageDefinitionInterface;
 use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\Tests\TestFileCreationTrait;
+use Drupal\system\Tests\Cache\AssertPageCacheContextsAndTagsTrait;
 use Drupal\user\RoleInterface;
 use Drupal\image\Entity\ImageStyle;
 
@@ -14,6 +16,12 @@
  */
 class ImageFieldDisplayTest extends ImageFieldTestBase {
 
+  use AssertPageCacheContextsAndTagsTrait;
+  use TestFileCreationTrait {
+    getTestFiles as drupalGetTestFiles;
+    compareFiles as drupalCompareFiles;
+  }
+
   protected $dumpHeaders = TRUE;
 
   /**
@@ -54,7 +62,7 @@ public function _testImageFieldFormatters($scheme) {
     $this->drupalGet("admin/structure/types/manage/article/display");
 
     // Test for existence of link to image styles configuration.
-    $this->drupalPostAjaxForm(NULL, [], "{$field_name}_settings_edit");
+    $this->drupalPostForm(NULL, [], "{$field_name}_settings_edit");
     $this->assertLinkByHref(\Drupal::url('entity.image_style.collection'), 0, 'Link to image styles configuration is found');
 
     // Remove 'administer image styles' permission from testing admin user.
@@ -65,7 +73,7 @@ public function _testImageFieldFormatters($scheme) {
     $this->drupalGet("admin/structure/types/manage/article/display");
 
     // Test for absence of link to image styles configuration.
-    $this->drupalPostAjaxForm(NULL, [], "{$field_name}_settings_edit");
+    $this->drupalPostForm(NULL, [], "{$field_name}_settings_edit");
     $this->assertNoLinkByHref(\Drupal::url('entity.image_style.collection'), 'Link to image styles configuration is absent when permissions are insufficient');
 
     // Restore 'administer image styles' permission to testing admin user
@@ -258,6 +266,7 @@ public function testImageFieldSettings() {
 
     $nid = $this->uploadNodeImage($test_image, $field_name, 'article', $alt);
     $this->drupalGet('node/' . $nid . '/edit');
+    // TODO: result is not "" as expected.
     $this->assertFieldByName($field_name . '[0][alt]', '', 'Alt field displayed on article form.');
     $this->assertFieldByName($field_name . '[0][title]', '', 'Title field displayed on article form.');
     // Verify that the attached image is being previewed using the 'medium'
@@ -324,7 +333,7 @@ public function testImageFieldSettings() {
     $edit = [
       'files[' . $field_name . '_2][]' => drupal_realpath($test_image->uri),
     ];
-    $this->drupalPostAjaxForm(NULL, $edit, $field_name . '_2_upload_button');
+    $this->drupalPostForm(NULL, $edit, $field_name . '_2_upload_button');
     $this->assertNoRaw('<input multiple type="file" id="edit-' . strtr($field_name, '_', '-') . '-2-upload" name="files[' . $field_name . '_2][]" size="22" class="js-form-file form-file">');
     $this->assertRaw('<input multiple type="file" id="edit-' . strtr($field_name, '_', '-') . '-3-upload" name="files[' . $field_name . '_3][]" size="22" class="js-form-file form-file">');
   }
diff --git a/core/modules/image/src/Tests/ImageFieldValidateTest.php b/core/modules/image/tests/src/Functional/ImageFieldValidateTest.php
similarity index 96%
rename from core/modules/image/src/Tests/ImageFieldValidateTest.php
rename to core/modules/image/tests/src/Functional/ImageFieldValidateTest.php
index 7e5ee9bae7..63de715681 100644
--- a/core/modules/image/src/Tests/ImageFieldValidateTest.php
+++ b/core/modules/image/tests/src/Functional/ImageFieldValidateTest.php
@@ -1,6 +1,8 @@
 <?php
 
-namespace Drupal\image\Tests;
+namespace Drupal\Tests\image\Functional;
+
+use Drupal\Tests\TestFileCreationTrait;
 
 /**
  * Tests validation functions such as min/max resolution.
@@ -8,6 +10,11 @@
  * @group image
  */
 class ImageFieldValidateTest extends ImageFieldTestBase {
+  use TestFileCreationTrait {
+    getTestFiles as drupalGetTestFiles;
+    compareFiles as drupalCompareFiles;
+  }
+
   /**
    * Test min/max resolution settings.
    */
diff --git a/core/modules/image/src/Tests/ImageOnTranslatedEntityTest.php b/core/modules/image/tests/src/Functional/ImageOnTranslatedEntityTest.php
similarity index 97%
rename from core/modules/image/src/Tests/ImageOnTranslatedEntityTest.php
rename to core/modules/image/tests/src/Functional/ImageOnTranslatedEntityTest.php
index e1f70d78a9..68ed0e2856 100644
--- a/core/modules/image/src/Tests/ImageOnTranslatedEntityTest.php
+++ b/core/modules/image/tests/src/Functional/ImageOnTranslatedEntityTest.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace Drupal\image\Tests;
+namespace Drupal\Tests\image\Functional;
 
 use Drupal\file\Entity\File;
+use Drupal\Tests\TestFileCreationTrait;
 
 /**
  * Uploads images to translated nodes.
@@ -11,6 +12,11 @@
  */
 class ImageOnTranslatedEntityTest extends ImageFieldTestBase {
 
+  use TestFileCreationTrait {
+    getTestFiles as drupalGetTestFiles;
+    compareFiles as drupalCompareFiles;
+  }
+
   /**
    * {@inheritdoc}
    */
diff --git a/core/modules/image/src/Tests/ImageStyleFlushTest.php b/core/modules/image/tests/src/Functional/ImageStyleFlushTest.php
similarity index 95%
rename from core/modules/image/src/Tests/ImageStyleFlushTest.php
rename to core/modules/image/tests/src/Functional/ImageStyleFlushTest.php
index 4e8cd2c779..070f199982 100644
--- a/core/modules/image/src/Tests/ImageStyleFlushTest.php
+++ b/core/modules/image/tests/src/Functional/ImageStyleFlushTest.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace Drupal\image\Tests;
+namespace Drupal\Tests\image\Functional;
 
 use Drupal\image\Entity\ImageStyle;
+use Drupal\Tests\TestFileCreationTrait;
 
 /**
  * Tests flushing of image styles.
@@ -11,6 +12,11 @@
  */
 class ImageStyleFlushTest extends ImageFieldTestBase {
 
+  use TestFileCreationTrait {
+    getTestFiles as drupalGetTestFiles;
+    compareFiles as drupalCompareFiles;
+  }
+
   /**
    * Given an image style and a wrapper, generate an image.
    */
diff --git a/core/modules/image/src/Tests/ImageStylesPathAndUrlTest.php b/core/modules/image/tests/src/Functional/ImageStylesPathAndUrlTest.php
similarity index 97%
rename from core/modules/image/src/Tests/ImageStylesPathAndUrlTest.php
rename to core/modules/image/tests/src/Functional/ImageStylesPathAndUrlTest.php
index 44254c6141..05164e8623 100644
--- a/core/modules/image/src/Tests/ImageStylesPathAndUrlTest.php
+++ b/core/modules/image/tests/src/Functional/ImageStylesPathAndUrlTest.php
@@ -1,16 +1,22 @@
 <?php
 
-namespace Drupal\image\Tests;
+namespace Drupal\Tests\image\Functional;
 
 use Drupal\image\Entity\ImageStyle;
-use Drupal\simpletest\WebTestBase;
+use Drupal\Tests\BrowserTestBase;
+use Drupal\Tests\TestFileCreationTrait;
 
 /**
  * Tests the functions for generating paths and URLs for image styles.
  *
  * @group image
  */
-class ImageStylesPathAndUrlTest extends WebTestBase {
+class ImageStylesPathAndUrlTest extends BrowserTestBase {
+
+  use TestFileCreationTrait {
+    getTestFiles as drupalGetTestFiles;
+    compareFiles as drupalCompareFiles;
+  }
 
   /**
    * Modules to enable.
diff --git a/core/modules/image/src/Tests/ImageThemeFunctionTest.php b/core/modules/image/tests/src/Functional/ImageThemeFunctionTest.php
similarity index 95%
rename from core/modules/image/src/Tests/ImageThemeFunctionTest.php
rename to core/modules/image/tests/src/Functional/ImageThemeFunctionTest.php
index 54c5c64a19..28320de4ce 100644
--- a/core/modules/image/src/Tests/ImageThemeFunctionTest.php
+++ b/core/modules/image/tests/src/Functional/ImageThemeFunctionTest.php
@@ -1,6 +1,6 @@
 <?php
 
-namespace Drupal\image\Tests;
+namespace Drupal\Tests\image\Functional;
 
 use Drupal\Core\Field\FieldStorageDefinitionInterface;
 use Drupal\Core\Url;
@@ -8,15 +8,21 @@
 use Drupal\field\Entity\FieldConfig;
 use Drupal\file\Entity\File;
 use Drupal\image\Entity\ImageStyle;
-use Drupal\simpletest\WebTestBase;
 use Drupal\field\Entity\FieldStorageConfig;
+use Drupal\Tests\BrowserTestBase;
+use Drupal\Tests\TestFileCreationTrait;
 
 /**
  * Tests image theme functions.
  *
  * @group image
  */
-class ImageThemeFunctionTest extends WebTestBase {
+class ImageThemeFunctionTest extends BrowserTestBase {
+
+  use TestFileCreationTrait {
+    getTestFiles as drupalGetTestFiles;
+    compareFiles as drupalCompareFiles;
+  }
 
   /**
    * Modules to enable.
@@ -103,6 +109,7 @@ public function testImageFormatterTheme() {
     // link options.
     $element = $base_element;
     $element['#item']->alt = '';
+    // TODO setRawContent.
     $this->setRawContent($renderer->renderRoot($element));
     $elements = $this->xpath('//a[@href=:path]/img[@class="image-style-test" and @src=:url and @width=:width and @height=:height and @alt=""]', [':path' => base_path() . $path, ':url' => $url, ':width' => $image->getWidth(), ':height' => $image->getHeight()]);
     $this->assertEqual(count($elements), 1, 'theme_image_formatter() correctly renders without title, alt, or path options.');
@@ -111,6 +118,7 @@ public function testImageFormatterTheme() {
     $fragment = $this->randomMachineName();
     $element = $base_element;
     $element['#url'] = Url::fromRoute('<none>', [], ['fragment' => $fragment]);
+    // TODO setRawContent.
     $this->setRawContent($renderer->renderRoot($element));
     $elements = $this->xpath('//a[@href=:fragment]/img[@class="image-style-test" and @src=:url and @width=:width and @height=:height and @alt=""]', [
       ':fragment' => '#' . $fragment,
@@ -146,6 +154,7 @@ public function testImageStyleTheme() {
     ];
 
     $element = $base_element;
+    // TODO setRawContent.
     $this->setRawContent($renderer->renderRoot($element));
     $elements = $this->xpath('//img[@class="image-style-image-test" and @src=:url and @alt=""]', [':url' => $url]);
     $this->assertEqual(count($elements), 1, 'theme_image_style() renders an image correctly.');
@@ -153,6 +162,7 @@ public function testImageStyleTheme() {
     // Test using theme_image_style() with a NULL value for the alt option.
     $element = $base_element;
     $element['#alt'] = NULL;
+    // TODO setRawContent.
     $this->setRawContent($renderer->renderRoot($element));
     $elements = $this->xpath('//img[@class="image-style-image-test" and @src=:url]', [':url' => $url]);
     $this->assertEqual(count($elements), 1, 'theme_image_style() renders an image correctly with a NULL value for the alt option.');
diff --git a/core/modules/image/src/Tests/QuickEditImageControllerTest.php b/core/modules/image/tests/src/Functional/QuickEditImageControllerTest.php
similarity index 92%
rename from core/modules/image/src/Tests/QuickEditImageControllerTest.php
rename to core/modules/image/tests/src/Functional/QuickEditImageControllerTest.php
index 870c1bb5d5..aecc7346cc 100644
--- a/core/modules/image/src/Tests/QuickEditImageControllerTest.php
+++ b/core/modules/image/tests/src/Functional/QuickEditImageControllerTest.php
@@ -1,16 +1,16 @@
 <?php
 
-namespace Drupal\image\Tests;
+namespace Drupal\Tests\image\Functional;
 
+use Drupal\Tests\BrowserTestBase;
 use Drupal\Tests\image\Kernel\ImageFieldCreationTrait;
-use Drupal\simpletest\WebTestBase;
 
 /**
  * Tests the endpoints used by the "image" in-place editor.
  *
  * @group image
  */
-class QuickEditImageControllerTest extends WebTestBase {
+class QuickEditImageControllerTest extends BrowserTestBase {
 
   use ImageFieldCreationTrait;
 
@@ -77,8 +77,12 @@ public function testAccess() {
     ]);
     $this->drupalGet('quickedit/image/info/node/' . $node->id() . '/' . $this->fieldName . '/' . $node->language()->getId() . '/default');
     $this->assertResponse('403');
-    $this->drupalPost('quickedit/image/upload/node/' . $node->id() . '/' . $this->fieldName . '/' . $node->language()->getId() . '/default', 'application/json', []);
-    $this->assertResponse('403');
+
+    /** @var \Symfony\Component\BrowserKit\Client $client */
+    $client = $this->getSession()->getDriver()->getClient();
+    $client->request('POST', '/quickedit/image/upload/node/' . $node->id() . '/' . $this->fieldName . '/' . $node->language()->getId() . '/default');
+    $this->assertEquals('403', $client->getResponse()->getStatus());
+
   }
 
   /**