Add color spin test for SkColorSpaceXformCanvas

Also changes behavior to treat nullptr srcs as sRGB.

Testing locally, it looks like 353 gms have no diffs from 8888.
There are 269 diffs - some are fine (gms that do color space stuff)
and some are bugs.

BUG=skia:

Change-Id: I55c2825f4f4b857e0b0a0ec050c6db82ac881492
Reviewed-on: https://skia-review.googlesource.com/9738
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Matt Sarett <msarett@google.com>

1 files changed, 6 insertions, 1 deletions

diff --git a/gm/imagemasksubset.cpp b/gm/imagemasksubset.cpp
index 80282787da..2d0d12038c 100644
--- a/gm/imagemasksubset.cpp
+++ b/gm/imagemasksubset.cpp
@@ -34,7 +34,12 @@ public:
             return false;
         }
 
-        make_mask(SkSurface::MakeRasterDirect(info, pixels, rowBytes));
+        SkImageInfo surfaceInfo = info;
+        if (kAlpha_8_SkColorType == info.colorType()) {
+            surfaceInfo = surfaceInfo.makeColorSpace(nullptr);
+        }
+
+        make_mask(SkSurface::MakeRasterDirect(surfaceInfo, pixels, rowBytes));
         return true;
     }