Resolve "Mark commented lines when feedback is hidden"

Closes #160 (closed)

frontend/src/components/submission_notes/SubmissionCorrection.vue

@@ -172,8 +172,12 @@ export default {
       }, 5e3)
     },
     hasHiddenComment (lineNo) {
-      return !this.showFeedback && this.origFeedback[lineNo]
+      const hasOrigComment = this.origFeedback && this.origFeedback[lineNo]
         && this.origFeedback[lineNo].length > 0
+
+      const hasUpdatedComment = this.updatedFeedback && this.updatedFeedback[lineNo]
+
+      return !this.showFeedback && (hasOrigComment || hasUpdatedComment)
     },
     init () {
       SubmissionNotes.RESET_STATE()