Update to Drupal 8.2.2. For more information, see https://www.drupal.org/project/drupal/releases/8.2.2

core/modules/editor/tests/editor_private_test/config/install/editor.editor.private_images.yml

@@ -0,0 +1,34 @@
+format: private_images
+status: true
+langcode: en
+editor: ckeditor
+settings:
+  toolbar:
+    rows:
+      -
+        -
+          name: Media
+          items:
+            - DrupalImage
+        -
+          name: Tools
+          items:
+            - Source
+  plugins:
+    language:
+      language_list: un
+    stylescombo:
+      styles: ''
+image_upload:
+  status: true
+  scheme: private
+  directory: ''
+  max_size: ''
+  max_dimensions:
+    width: null
+    height: null
+dependencies:
+  config:
+    - filter.format.private_images
+  module:
+    - ckeditor

core/modules/editor/tests/editor_private_test/config/install/filter.format.private_images.yml

@@ -0,0 +1,23 @@
+format: private_images
+name: 'Private images'
+status: true
+langcode: en
+filters:
+  editor_file_reference:
+    id: editor_file_reference
+    provider: editor
+    status: true
+    weight: 0
+    settings: {  }
+  filter_html:
+    id: filter_html
+    provider: filter
+    status: false
+    weight: -10
+    settings:
+      allowed_html: '<img src alt data-entity-type data-entity-uuid>'
+      filter_html_help: true
+      filter_html_nofollow: false
+dependencies:
+  module:
+    - editor

core/modules/editor/tests/editor_private_test/editor_private_test.info.yml

@@ -0,0 +1,9 @@
+name: 'Text Editor Private test'
+type: module
+description: 'Support module for the Text Editor Private module tests.'
+core: 8.x
+package: Testing
+version: VERSION
+dependencies:
+  - filter
+  - ckeditor