Fix parallel diff lines content.

app/assets/javascripts/diffs/components/diff_table_cell.vue

@@ -11,6 +11,8 @@ import {
   LINE_HOVER_CLASS_NAME,
   LINE_UNFOLD_CLASS_NAME,
   INLINE_DIFF_VIEW_TYPE,
+  LINE_POSITION_LEFT,
+  LINE_POSITION_RIGHT,
 } from '../constants';
 
 export default {
@@ -65,11 +67,17 @@ export default {
   computed: {
     ...mapGetters(['isLoggedIn']),
     normalizedLine() {
+      let normalizedLine;
+
       if (this.diffViewType === INLINE_DIFF_VIEW_TYPE) {
-        return this.line;
+        normalizedLine = this.line;
+      } else if (this.linePosition === LINE_POSITION_LEFT) {
+        normalizedLine = this.line.left;
+      } else if (this.linePosition === LINE_POSITION_RIGHT) {
+        normalizedLine = this.line.right;
       }
 
-      return this.lineType === OLD_LINE_TYPE ? this.line.left : this.line.right;
+      return normalizedLine;
     },
     isMatchLine() {
       return this.normalizedLine.type === MATCH_LINE_TYPE;

app/assets/javascripts/diffs/components/parallel_diff_table_row.vue

@@ -118,6 +118,7 @@ export default {
       :diff-file="diffFile"
       :line="line"
       :is-content-line="true"
+      :line-position="linePositionLeft"
       :line-type="parallelViewLeftLineType"
       :diff-view-type="parallelDiffViewType"
       class="line_content parallel left-side"
@@ -139,6 +140,7 @@ export default {
       :diff-file="diffFile"
       :line="line"
       :is-content-line="true"
+      :line-position="linePositionRight"
       :line-type="line.right.type"
       :diff-view-type="parallelDiffViewType"
       class="line_content parallel right-side"