Fixed bugs with diff comment avatars

The comment button on commit view was way out to the left side because
the element that renders the diff avatars was rendering when it shouldnt
be

When commenting on a discussion on the discussions tab it would try to
render the avatar & in some cases work correctly even though it shouldnt
be possible for this to happen. Changed the if statement to take this
into account

Closes #29237, #29238, #29243

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

@@ -5,6 +5,7 @@
 - line_code = diff_file.line_code(line)
 - if discussions && !line.meta?
   - discussion = discussions[line_code]
+  - show_discussion_avatars = discussion && discussion.resolvable? && !plain
 %tr.line_holder{ class: type, id: (line_code unless plain) }
   - case type
   - when 'match'
@@ -14,13 +15,13 @@
     %td.new_line.diff-line-num
     %td.line_content.match= line.text
   - else
-    %td.old_line.diff-line-num.js-avatar-container{ class: type, data: { linenumber: line.old_pos } }
+    %td.old_line.diff-line-num{ class: [type, ("js-avatar-container" if show_discussion_avatars)], data: { linenumber: line.old_pos } }
       - link_text = type == "new" ? " " : line.old_pos
       - if plain
         = link_text
       - else
         %a{ href: "##{line_code}", data: { linenumber: link_text } }
-      - if discussion && !plain
+      - if show_discussion_avatars
         %diff-note-avatars{ "discussion-id" => discussion.id }
     %td.new_line.diff-line-num{ class: type, data: { linenumber: line.new_pos } }
       - link_text = type == "old" ? " " : line.new_pos

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

@@ -20,7 +20,7 @@
             - left_position = diff_file.position(left)
             %td.old_line.diff-line-num.js-avatar-container{ id: left_line_code, class: left.type, data: { linenumber: left.old_pos } }
               %a{ href: "##{left_line_code}", data: { linenumber: left.old_pos } }
-              - if discussion_left
+              - if discussion_left && discussion_left.resolvable?
                 %diff-note-avatars{ "discussion-id" => discussion_left.id }
             %td.line_content.parallel.noteable_line{ class: left.type, data: diff_view_line_data(left_line_code, left_position, 'old') }= diff_line_content(left.text)
         - else
@@ -39,7 +39,7 @@
             - right_position = diff_file.position(right)
             %td.new_line.diff-line-num.js-avatar-container{ id: right_line_code, class: right.type, data: { linenumber: right.new_pos } }
               %a{ href: "##{right_line_code}", data: { linenumber: right.new_pos } }
-              - if discussion_right
+              - if discussion_right && discussion_right.resolvable?
                 %diff-note-avatars{ "discussion-id" => discussion_right.id }
             %td.line_content.parallel.noteable_line{ class: right.type, data: diff_view_line_data(right_line_code, right_position, 'new') }= diff_line_content(right.text)
         - else