Update accessibility for popup

- Content description includes count of notifications.
- Notifications have a dismiss action.
- All icons that support shortcuts will have action to show
  shortcut menu, since there will be system shortcuts even if
  there are no deep shortcuts.

Bug: 36564782
Change-Id: I51b085fa26754f2dcd93c7db6548f2edf054f494

src/com/android/launcher3/BubbleTextView.java

@@ -659,14 +659,6 @@ public class BubbleTextView extends TextView implements ItemInfoUpdateReceiver {
         }
     }
 
-    /**
-     * Returns true if the view can show custom shortcuts.
-     */
-    public boolean hasDeepShortcuts() {
-        return !mLauncher.getPopupDataProvider().getShortcutIdsForItem((ItemInfo) getTag())
-                .isEmpty();
-    }
-
     /**
      * Interface to be implemented by the grand parent to allow click shadow effect.
      */