Measure time flushing completed videos to storage

Measure the fsync() time at the end of video recording for mpeg4 files.
This is intended to be a short term measurement.
Timing is logged to logcat.

Bug: 174770856
Test: Video Capture & read logcat
Change-Id: I786521ec705c13e315627e2cfe1f63448b62567f
1 file changed