Help msvs compile SkColorSpaceXform faster

Allowing MSVS to choose to not inline color_xform_RGBA
will prevent the complexity from exploding.

BUG=skia:

GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=3884

Change-Id: I31ab0754c6cc375d6d0e71ceb16afef1927bb4e3
Reviewed-on: https://skia-review.googlesource.com/3884
Reviewed-by: Mike Klein <mtklein@chromium.org>
Commit-Queue: Matt Sarett <msarett@google.com>
1 file changed