Fix bug in autocomplete focus detection

https://goo.gl/j4Lr5w enabled conditional showing of autocomplete
suggestions based on focus of the autocomplete's child input. One case
in which the input is focused programmatically as opposed to through UI
interaction fell through the cracks.
This change addresses that case.

Change-Id: I24515557c3cf9af164991829746d597a2b769c84

polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete.html

@@ -55,7 +55,8 @@ limitations under the License.
         bind-value="{{text}}"
         placeholder="[[placeholder]]"
         on-keydown="_handleInputKeydown"
-        on-focus="_updateSuggestions"
+        on-focus="_onInputFocus"
+        on-blur="_onInputBlur"
         autocomplete="off" />
     <div
         id="suggestions"

polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete.js

@@ -117,14 +117,6 @@
 
     },
 
-    attached: function() {
-      this.listen(document.body, 'click', '_handleBodyClick');
-    },
-
-    detached: function() {
-      this.unlisten(document.body, 'click', '_handleBodyClick');
-    },
-
     get focusStart() {
       return this.$.input;
     },
@@ -147,6 +139,15 @@
       this._disableSuggestions = false;
     },
 
+    _onInputFocus: function() {
+      this._focused = true;
+      this._updateSuggestions();
+    },
+
+    _onInputBlur: function() {
+      this._focused = false;
+    },
+
     _updateSuggestions: function() {
       if (!this.text || this._disableSuggestions) { return; }
       if (this.text.length < this.threshold) {
@@ -228,18 +229,6 @@
       }
     },
 
-    _handleBodyClick: function(e) {
-      var eventPath = Polymer.dom(e).path;
-      for (var i = 0; i < eventPath.length; i++) {
-        if (eventPath[i] == this) {
-          this._focused = true;
-          return;
-        }
-      }
-      this._suggestions = [];
-      this._focused = false;
-    },
-
     _handleSuggestionTap: function(e) {
       this.$.cursor.setCursor(e.target);
       this._commit();

polygerrit-ui/app/elements/shared/gr-autocomplete/gr-autocomplete_test.html

@@ -266,6 +266,15 @@ limitations under the License.
       assert.isTrue(commitHandler.called);
     });
 
+    test('_focused flag properly triggered', function() {
+      flushAsynchronousOperations();
+      assert.isFalse(element._focused);
+      element.$.input.focus();
+      assert.isTrue(element._focused);
+      element.$.input.blur();
+      assert.isFalse(element._focused);
+    });
+
     test('_focused flag shows/hides the suggestions', function() {
       var suggestions = ['hello', 'its me'];
       assert.isTrue(element._computeSuggestionsHidden(suggestions, false));