Merge branch 'dm-copy-as-gfm-anchor-link' into 'master'

Correctly transform an anchor link to GFM when copying it

See merge request !9080

app/assets/javascripts/copy_as_gfm.js.es6

@@ -91,6 +91,9 @@ require('./lib/utils/common_utils');
       },
     },
     SanitizationFilter: {
+      'a[name]:not([href]):empty'(el, text) {
+        return el.outerHTML;
+      },
       'dl'(el, text) {
         let lines = text.trim().split('\n');
         // Add two spaces to the front of subsequent list items lines,

spec/features/copy_as_gfm_spec.rb

@@ -251,6 +251,8 @@ describe 'Copy as GFM', feature: true, js: true do
       'SanitizationFilter',
       <<-GFM.strip_heredoc
+      <a name="named-anchor"></a>
+      
       <sub>sub</sub>
       <dl>