Fix camera preview stopped after onResume().

This fix is for the blank camera preview blank after onPause() -> onResume().
1. Refined camera start up procedure by removing redundant camera startup
   thread.
2. Cleanup unused calls after aparted from gallery.

  bug:10189998

Change-Id: I13ffa24aff5069f0032cd4bc801548fccc63d0e7
9 files changed