MPEG4Writer:stop & notify,MediaMuxer:remove notify

1) MPEG4Writer.cpp, Whenever there are critical errors its better
   that the threads are stopped before notifying its client.
2) Recent code changes(ag/9886712) in MediaMuxer.cpp in R to receive
   notifications from writer threads, MIGHT lead to deadlock in a
   scenario when the client thread was waiting for the
   writeSampleData to complete while holding mLock, and a
   notification was sent from track threads or the main  writer
   thread to MediaMuxer without stopping the source and/or
   stopping the writer threads. Though tough to reproduce(if at all)
   it's a bad design that should be avoided to keep the code simple
   and less error prone. Now that MPEG4Writer either stops
   the source or stop all writer threads based on the severity of
   the errors, it would be reflected in the next writeSampleData
   or stop call from the client.  Hence, removed the code changes
   for notifying error from writer to MediaMuxer class.
3) Added logs in MediaWriter to get details of notifications with
   track id.

Bug: 157600876

Test: android.media.cts.MediaMuxerTest
Test: android.mediav2.cts.MuxerTest
Test: android.media.cts.MediaRecorderTest
Test: android.mediastress.cts.MediaMuxerStressTest

Change-Id: Idb8996134010669261fa638907b497c0cf70de6b