Prepare for partial release.

- Default to Rails::DeprecatedSanitizer in ActionView::Helpers::SanitizeHelper.
- Add upgrade notes.
- Add sanitizer to new applications Gemfiles.
- Remove 'rails-dom-testing' as a dependency.

1 files changed, 8 insertions, 3 deletions

diff --git a/actionview/lib/action_view/helpers/sanitize_helper.rb b/actionview/lib/action_view/helpers/sanitize_helper.rb
index 2268fe25c1..153c64d691 100644
--- a/actionview/lib/action_view/helpers/sanitize_helper.rb
+++ b/actionview/lib/action_view/helpers/sanitize_helper.rb
@@ -1,6 +1,6 @@
 require 'active_support/core_ext/object/try'
 require 'active_support/deprecation'
-require 'rails-html-sanitizer'
+require 'rails-deprecated_sanitizer'
 
 module ActionView
   # = Action View Sanitize Helpers
@@ -138,9 +138,14 @@ module ActionView
         end
 
         # Vendors the full, link and white list sanitizers.
-        # Strictly for backwards compatibility with html-scanner.
+        # This uses html-scanner for the HTML sanitization.
+        # In the next Rails version this will use Rails::Html::Sanitizer instead.
+        # To get this new behavior now, in your Gemfile, add:
+        #
+        #  gem 'rails-html-sanitizer'
+        #
         def sanitizer_vendor
-          Rails::Html::Sanitizer
+          Rails::DeprecatedSanitizer
         end
 
         def sanitized_allowed_tags