App Bubble custom icon support

* Add `Icon` argument to `BubbleController.showOrHideAppBubble` method
  to allow custom app icon
* Update `NoteTaskController` usages of the method

Test: atest BubblesTest NoteTaskControllerTest
Bug: 268351693
Change-Id: I3366a8e576ff87725e07090f38aec3cd11ad7d39