Use assigned variables better

app/views/discussions/_diff_with_notes.html.haml

@@ -9,7 +9,7 @@
     %table
       - discussions = { discussion.original_line_code => discussion }
       = render partial: "projects/diffs/line",
-        collection: discussion.highlighted_diff_lines,
+        collection: discussion.truncated_diff_lines,
         as: :line,
         locals: { diff_file: diff_file,
           discussions: discussions,

app/views/notify/_note_mr_or_commit_email.html.haml

@@ -3,12 +3,10 @@
 New comment
-- if @note.diff_note? && @note.diff_file
+- if @discussion && @discussion.diff_file
   on
   = link_to @note.diff_file.file_path, @target_url, class: 'details'
-\:
-
-- if @discussion
+  \:
   %table
     = render partial: "projects/diffs/line",
       collection: @discussion.truncated_diff_lines,

lib/gitlab/diff/file.rb

@@ -69,7 +69,7 @@ module Gitlab
         diff_refs.try(:head_sha)
       end
-      attr_writer :highlighted_diff_lines, :text_parsed_diff_lines
+      attr_writer :highlighted_diff_lines
       # Array of Gitlab::Diff::Line objects
       def diff_lines