Revert "Merge "HeadsUp: Only remove heads up if attached to window" into kk4.4-caf"

This reverts commit a264b8d294677dbeda2a94a67f02f4bd3fa4e1b4, reversing
changes made to 6888cb48046de65ba7cea0150deb2b22e8513e98.

Conflicts:

	packages/SystemUI/res/values-ru/slim_strings.xml