GitLab

veatest: Fixes for bitrate tests.

- introduce a minimum number of frames for bitrate tests; if a stream is
  too short, loop it over as many times as needed to reach that minimum
- instead of using additional black frames to flush the encoder at the
  end of encode, just rewind and reuse frames from the beginning;
  this also eliminates the need for the CS_FINISHING state;
- switch to a more demanding/varied stream for bitrate tests (bear)

- also move the starting point of encoder FPS calculation from Initialize()
  to after setting up the buffers to slightly better estimate actual encoder
  performance
- minor additions to the documentation of and fixes for input buffer size
  calculation
- add ifdefs to only check alignment on ARM

BUG=366158
TEST=run test, ensure bitrates converge properly on relevant platforms

Review URL: https://codereview.chromium.org/290643003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@272864 0039d316-1c4b-4281-b951-d872f2087c98