1 files changed, 39 insertions, 0 deletions
diff --git a/polygerrit-ui/app/elements/plugins/gr-change-metadata-api/gr-change-metadata-api.js b/polygerrit-ui/app/elements/plugins/gr-change-metadata-api/gr-change-metadata-api.js
new file mode 100644
index 0000000000..b550f73b62
--- /dev/null
+++ b/polygerrit-ui/app/elements/plugins/gr-change-metadata-api/gr-change-metadata-api.js
@@ -0,0 +1,39 @@
+/**
+ * @license
+ * Copyright (C) 2018 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+(function(window) {
+  'use strict';
+
+  function GrChangeMetadataApi(plugin) {
+    this._hook = null;
+    this.plugin = plugin;
+  }
+
+  GrChangeMetadataApi.prototype._createHook = function() {
+    this._hook = this.plugin.hook('change-metadata-item');
+  };
+
+  GrChangeMetadataApi.prototype.onLabelsChanged = function(callback) {
+    if (!this._hook) {
+      this._createHook();
+    }
+    this._hook.onAttached(element =>
+        this.plugin.attributeHelper(element).bind('labels', callback));
+    return this;
+  };
+
+  window.GrChangeMetadataApi = GrChangeMetadataApi;
+})(window);