Add unit tests for SkImage::colorSpace()

BUG=skia:

Change-Id: I1cb4bd1b5ca02f37bd08679803cf645b4d5ecc00
Reviewed-on: https://skia-review.googlesource.com/9297
Reviewed-by: Mike Reed <reed@google.com>
Commit-Queue: Matt Sarett <msarett@google.com>
1 file changed