Fix bug 5300621 - Share menu disappears in gallery

ActionProviders (or action views) unfortunately had no way to report
that they had opened a sub-UI that would affect menu visibility
listeners used to hide action bars when not in use. This caused the
Gallery UI to hide its action bar when the share popup was open.

Add hidden API (to be made public later) to ActionProvider that can be
used to inform the menu system that a sub UI has opened or
closed. Account for this in menu visibility callbacks. Fix
ShareActionProvider to use this when its popup windows open and close.

Fix a regression where submenus were not properly reporting visibility
changes.

Change-Id: Ia6f45fb463ad106105c40d01f141c2e5c8b96f78