Reimplements I444ToARGB as a matrix function.
new I444ToABGR as matrix functions with wrappers and any functions.
Allows for future J444 and H444 versions.
I444ToABGR user level function added.

BUG=libyuv:490, libyuv:449
R=harryjin@google.com

Review URL: https://codereview.chromium.org/1355733002 .