stagefright: Handle acquireWakeLock failure case

When the power service is not running, acquireWakeLock fails, but
TimedEventQueue still keeps a reference count to a non-existent
wakelock. This causes an assertion failure when trying to free the
wakelock. Only increment the reference count and save the wakelock
reference on successful acquire.

CRs-Fixed: 640796
Change-Id: I441bf8d4c3520eb6ce8a378d2744913de0a44f55
audio: Fixed mBytesRemaining when partial buffers are sent

- When AudioFlinger writes partial buffers to HAL,
  write() on HAl returns period_size if bytes written
  are less than period_size. This is causing
  mBytesRemaining to be negative

- Fix is to check the return value of write() and
  set mBytesRemaining and mBytesWritten correctly

Change-Id: Ibd3cb138c0d4669e9e17c22f6b2c80804c6499a5
CRs-fixed: 611119