Add concept of auto generated messages to PolyGerrit UI (front end)

This change allows users to hide all robot generated messages in the
Polygerrit UI.

Feature: Issue 4595
Change-Id: I80f11dc48d15bd59a24fd008f9db72ff37cfdbda

polygerrit-ui/app/elements/change/gr-messages-list/gr-messages-list_test.html

@@ -78,7 +78,7 @@ limitations under the License.
         assert.isTrue(allMessageEls[i].expanded);
       }
 
-      MockInteractions.tap(element.$$('.header gr-button'));
+      MockInteractions.tap(element.$$('#collapse-messages'));
       allMessageEls =
           Polymer.dom(element.root).querySelectorAll('gr-message');
       for (var i = 0; i < allMessageEls.length; i++) {
@@ -86,6 +86,11 @@ limitations under the License.
       }
     });
 
+    test('hide messages does not appear when no automated messages',
+        function() {
+      assert.isOk(element.$$('#automatedMessageToggle[hidden]'));
+    });
+
     test('scroll to message', function() {
       var allMessageEls =
           Polymer.dom(element.root).querySelectorAll('gr-message');
@@ -204,4 +209,77 @@ limitations under the License.
       assert.deepEqual(messageElements[2].comments, {});
     });
   });
+
+  suite('gr-messages-list automate tests', function() {
+    var element;
+    var messages;
+
+    var randomMessage = function(opt_params) {
+      var params = opt_params || {};
+      var author1 = {
+        _account_id: 1115495,
+        name: 'Andrew Bonventre',
+        email: 'andybons@chromium.org',
+      };
+      return {
+        id: params.id || Math.random().toString(),
+        date: params.date || '2016-01-12 20:28:33.038000',
+        message: params.message || Math.random().toString(),
+        _revision_number: params._revision_number || 1,
+        author: params.author || author1,
+        tag: 'autogenerated:gerrit:replace',
+      };
+    };
+
+    setup(function() {
+      stub('gr-rest-api-interface', {
+        getConfig: function() { return Promise.resolve({}); },
+        getLoggedIn: function() { return Promise.resolve(false); },
+      });
+      element = fixture('basic');
+      messages = _.times(3, randomMessage);
+      element.messages = messages;
+      flushAsynchronousOperations();
+    });
+
+    test('hide autogenerated button is not hidden', function() {
+      assert.isNotOk(element.$$('#automatedMessageToggle[hidden]'));
+    });
+
+    test('autogenerated messages are not hidden initially', function() {
+      var allHiddenMessageEls =
+          Polymer.dom(element.root).querySelectorAll('gr-message[hidden]');
+
+      //There are no hidden messages.
+      assert.isFalse(!!allHiddenMessageEls.length);
+    });
+
+    test('autogenerated messages are hidden after clicking hide button',
+        function() {
+      var allHiddenMessageEls =
+          Polymer.dom(element.root).querySelectorAll('gr-message[hidden]');
+
+      element._hideAutomated = false;
+      MockInteractions.tap(element.$$('#automatedMessageToggle'));
+      allHiddenMessageEls =
+          Polymer.dom(element.root).querySelectorAll('gr-message[hidden]');
+
+      //Autogenerated messages are now hidden.
+      assert.isTrue(!!allHiddenMessageEls.length);
+    });
+
+    test('autogenerated messages are not hidden after clicking show button',
+        function() {
+      var allHiddenMessageEls =
+          Polymer.dom(element.root).querySelectorAll('gr-message[hidden]');
+
+      element._hideAutomated = true;
+      MockInteractions.tap(element.$$('#automatedMessageToggle'));
+      allHiddenMessageEls =
+          Polymer.dom(element.root).querySelectorAll('gr-message[hidden]');
+
+      //Autogenerated messages are now hidden.
+      assert.isFalse(!!allHiddenMessageEls.length);
+    });
+  });
 </script>