Add a different color for robot comments

* If comment thread ends with robot comment change color

Change-Id: Idc0c29374fc5a2d500b865920c67a7f883a2094e

polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.html

@@ -58,6 +58,9 @@ limitations under the License.
       #container.unresolved {
         background-color: var(--unresolved-comment-background-color);
       }
+      #container.robotComment {
+        background-color: var(--robot-comment-background-color);
+      }
       #commentInfoContainer {
         border-top: 1px dotted var(--border-color);
         display: flex;
@@ -82,7 +85,7 @@ limitations under the License.
         <span class="descriptionText">Patchset [[patchNum]]</span>
       </div>
     </template>
-    <div id="container" class$="[[_computeHostClass(unresolved)]]">
+    <div id="container" class$="[[_computeHostClass(unresolved, isRobotComment)]]">
       <template id="commentList" is="dom-repeat" items="[[_orderedComments]]"
           as="comment">
         <gr-comment

polygerrit-ui/app/elements/shared/gr-comment-thread/gr-comment-thread.js

@@ -137,6 +137,11 @@
         _lastComment: Object,
         _orderedComments: Array,
         _projectConfig: Object,
+        isRobotComment: {
+          type: Boolean,
+          value: false,
+          reflectToAttribute: true,
+        },
       };
     }
 
@@ -221,6 +226,7 @@
         this._lastComment = this._getLastComment();
         this.unresolved = this._lastComment.unresolved;
         this.hasDraft = this._lastComment.__draft;
+        this.isRobotComment = !!(this._lastComment.robot_id);
       }
     }
 
@@ -498,6 +504,9 @@
     }
 
     _computeHostClass(unresolved) {
+      if (this.isRobotComment) {
+        return 'robotComment';
+      }
       return unresolved ? 'unresolved' : '';
     }
 

polygerrit-ui/app/styles/themes/app-theme.html

@@ -45,6 +45,7 @@ html {
   --assignee-highlight-color: #fcfad6;
   --chip-background-color: #eee;
   --comment-background-color: #fcfad6;
+  --robot-comment-background-color: #e8f0fe;
   --default-button-background-color: white;
   --dialog-background-color: white;
   --dropdown-background-color: white;

polygerrit-ui/app/styles/themes/dark-theme.html

@@ -45,6 +45,7 @@ limitations under the License.
       --assignee-highlight-color: #3a361c;
       --chip-background-color: #131416;
       --comment-background-color: #0b162b;
+      --robot-comment-background-color: #e8f0fe;
       --default-button-background-color: #3c4043;
       --dialog-background-color: #131416;
       --dropdown-background-color: #131416;