Add more jsdoc for closure checks

1. add `@extends` for all polymer elements
2. add `@override` for all lifecycle methods
3. fix a wrong type in gr-auth

Change-Id: Id9dea76b169197084d2e0b5f267459cdc4aaec3e

polygerrit-ui/app/behaviors/gr-tooltip-behavior/gr-tooltip-behavior.js

@@ -49,6 +49,7 @@
       },
     },
 
+    /** @override */
     detached() {
       this._handleHideTooltip();
     },

polygerrit-ui/app/behaviors/keyboard-shortcut-behavior/keyboard-shortcut-behavior.html

@@ -540,6 +540,7 @@ shortcuts are.
         }
       },
 
+      /** @override */
       attached() {
         const shortcuts = shortcutManager.attachHost(this);
         if (!shortcuts) { return; }
@@ -559,6 +560,7 @@ shortcuts are.
         }
       },
 
+      /** @override */
       detached() {
         if (shortcutManager.detachHost(this)) {
           this.removeOwnKeyBindings();