Add a new test stream for video_encode_accelerator_unittest.

BUG=366158
NOTRY=true

Review URL: https://codereview.chromium.org/299833005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@272482 0039d316-1c4b-4281-b951-d872f2087c98

media/test/data/README

@@ -144,3 +144,8 @@ red-green.h264.md5:
   These differ between implementations because color space-converted frames are
   not specified to the last bit and GLES shader/texture filtering
   precision varies.
+
+// VEA test files:
+bear_320x192_40frames.yuv
+  First 40 raw i420 frames of bear-1280x720.mp4 scaled down to 320x192 for
+  video_encode_accelerator_unittest.