stagefright: add rendering statistics

 - adds extra fps statistics
 - report via dumpsys
 - prints statistics before reset at the end of playback onto
   logcat
 - adds resume latency, from play_l to render
 - adds seek latency, from seek_l to render
 - enables using persist.debug.sf.statistics 1
 - prints all statistics when seek or resume is issued

Change-Id: I6fa34f3d0180c1b8bbad40da42bd241fb89e6866