Revert "Notify DecorContentParent about content change"

This reverts commit e96b939b83f334114847e2b1c258135f159792ad.

Reason for revert: Droidmonitor created revert due to b/346785755.

Change-Id: Ieaed6a2b8a465af0f636676d1c7d1ae94924d733
3 files changed