Now returning html if html is blank? in FullSanitizer and WhiteListSanitizer....

Now returning html if html is blank? in FullSanitizer and WhiteListSanitizer. This means it'll return false if called with false, however that is not a valid use case.

actionview/lib/action_view/helpers/sanitize_helper/sanitizers.rb

 require 'active_support/core_ext/class/attribute'
+require 'active_support/core_ext/object/blank'
 require 'active_support/deprecation'
 require 'action_view/helpers/sanitize_helper/scrubbers'
 
@@ -25,7 +26,7 @@ def remove_xpaths(html, xpaths)
   class FullSanitizer < Sanitizer
     def sanitize(html, options = {})
       return unless html
-      return html if html.empty?
+      return html if html.blank?
 
       Loofah.fragment(html).tap do |fragment|
         remove_xpaths(fragment, XPATHS_TO_REMOVE)
@@ -51,6 +52,7 @@ def initialize
 
     def sanitize(html, options = {})
       return unless html
+      return html if html.blank?
 
       loofah_fragment = Loofah.fragment(html)
 

actionview/test/template/sanitizers_test.rb

@@ -219,7 +219,7 @@ def test_should_allow_custom_tags_with_custom_attributes
   def test_should_raise_argument_error_if_tags_is_not_enumerable
     sanitizer = ActionView::WhiteListSanitizer.new
     e = assert_raise(ArgumentError) do
-      sanitizer.sanitize('', :tags => 'foo')
+      sanitizer.sanitize('<a>some html</a>', :tags => 'foo')
     end
 
     assert_equal "You should pass :tags as an Enumerable", e.message
@@ -228,7 +228,7 @@ def test_should_raise_argument_error_if_tags_is_not_enumerable
   def test_should_raise_argument_error_if_attributes_is_not_enumerable
     sanitizer = ActionView::WhiteListSanitizer.new
     e = assert_raise(ArgumentError) do
-      sanitizer.sanitize('', :attributes => 'foo')
+      sanitizer.sanitize('<a>some html</a>', :attributes => 'foo')
     end
 
     assert_equal "You should pass :attributes as an Enumerable", e.message
@@ -242,7 +242,7 @@ def scrub(node); node.name = 'h1'; end
     end
 
     assert_raise Loofah::ScrubberNotFound do
-      sanitizer.sanitize('', :scrubber => scrubber)
+      sanitizer.sanitize('<a>some html</a>', :scrubber => scrubber)
     end
   end