Revert "Keep source bitmap id for received ashmem bitmaps"

This reverts commit 332540d2.

Reason for revert: DroidMonitor: Potential culprit for http://b/406334585 - 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: I19d23c7d469a8b09593634502a6687c563ef3bba