rm vp9_frame_parallel_test.cc

VPX_CODEC_USE_FRAME_THREADING was made a no-op in:
01d23109a vp9: make VPX_CODEC_USE_FRAME_THREADING a no-op

and the tests in this file have been disabled since:
6ab0870d4 disable VP9MultiThreadedFrameParallel tests

BUG=webm:1395

Change-Id: I2c7a250acb65cf9522cf8a7bb724bb92070e41c6
2 files changed