Force white theme when viewing diffs. #3945

app/views/projects/diffs/_parallel_view.html.haml

 / Side-by-side diff view
-%div.text-file.diff-wrap-lines.code.file-content.js-syntax-highlight{ class: user_color_scheme }
+%div.text-file.diff-wrap-lines.code.file-content.js-syntax-highlight.white
   %table
     - parallel_diff(diff_file, index).each do |line|
       - type_left = line[0]

app/views/projects/diffs/_text_file.html.haml

@@ -3,7 +3,7 @@
   .suppressed-container
     %a.show-suppressed-diff.js-show-suppressed-diff Changes suppressed. Click to show.
 
-%table.text-file.code.js-syntax-highlight{ class: [user_color_scheme, too_big ? 'hide' : ''] }
+%table.text-file.code.js-syntax-highlight.white{ class: too_big ? 'hide' : '' }
 
   - last_line = 0
   - diff_file.highlighted_diff_lines.each_with_index do |line, index|