There's a common misconception (even across the framework) that
View#onVisibilityChanged determines and reports visibility on 'this'
up to the changed view and the total visibility within the
window. Knowing this is useful for things like starting/stopping
animations. onVisibilityChanged only reports the visibility for the
specific changed view, not the effects that would have down the tree.
Add onVisibilityAggregated to report what some code thought it was
getting already, and move ImageView and ProgressBar over to using it.
Bug 27461617
Change-Id: I433f41de453e27a53f907f1d9805350f30f31de9
41d9690c3e