frameworks/base: Add rendering statistics to Stagefright (Adapted)

- this is an adaptation of change 514 (I88dd988c9) from HC to ICS
- functionality is the same as the forementioned patch
- added all statistics properties for AwesomePlayer into
  Google's Stats struct
- acquire locking before modifying/accessing mStats values
- moved mStatistics check in AwesomePlayer to inside the log functions

Change-Id: I553823b22403a0e5e9fc3998a27a54fec9e1b5c4