Revert^2 "Notify DecorContentParent about content change"

This reverts commit 7a637db1accfbbcc55ac06247497521d2c1ce518.

Reason for revert: DroidMonitor: Potential culprit for b/346868502 - verifying through ABTD before revert submission. This is part of the standard investigation process, and does not mean your CL will be reverted.

Change-Id: I7ca220b5c8d33c145ba4e92d4632e90cc0b9fedd
3 files changed