File video capture device supports MJPEG format

Because input file can be a MJPEG stream video which concatenates many
MJPEG/JPEG images directly, jpeg parser should support to detect EOI
marker.

BUG=517303
TEST=test on peach_pi and squawks with Y4M and JPEG files. Make sure jpeg
histogram is correct while playing JPEG file.

Review URL: https://codereview.chromium.org/1291933002

Cr-Commit-Position: refs/heads/master@{#344749}
6 files changed