zero a2b values of stock profiles

This makes more profiles bitwise identical with skcms_sRGB_profile(),
as shown in the new unit test, which failed before.

This showed up in ic_lockscreen_google_focused,
but moved the cost of skcms_Transform() from tiny to ~zero.

Bug: skia:8278

Change-Id: I2b6737d7a059eb228b1a8e92bf4adbea45afc411
Reviewed-on: https://skia-review.googlesource.com/150244
Auto-Submit: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Osman <brianosman@google.com>
2 files changed