SoundRecorder: Avoid error when record start and stop comes too closely.

If record start and stop come too closely, internal exception error
will be threw. Add necessary delay before back key is pressed in
recording state to avoid recording internal error.

CRs-Fixed: 642195
Change-Id: Ia24c4a45ce4cfdab05d269ec118dcf48f74beecc
MMS: Exit app after recording, if from MMS.

When add record audio in MMS, it can not back to MMS
automatically after recording.
Add a flag mExitAfterRecord, if from MMS, the value is true,
exit app and back to MMS after recording, if not from MMS,
the value is false, do not exit app after recording.

Change-Id: Id554bfd2a3f7128edd4f8825cfe1a1277831311d
CRs-Fixed: 638039