Miscellaneous color space refactors

src/core/SkColorSpaceXform.h

Index: src/core/SkColorSpaceXform.h
diff --git a/src/core/SkColorSpaceXform.h b/src/core/SkColorSpaceXform.h
index 061bc366fbfca46009e1f6d703aeb00b129ffa45..0947e0848e5d46364bf0d59b8929446fc828f1a9 100644
--- a/src/core/SkColorSpaceXform.h
+++ b/src/core/SkColorSpaceXform.h
@@ -55,7 +55,7 @@ private:
     const float*         fSrcGammaTables[3];
     float                fSrcGammaTableStorage[3 * 256];
 
-    float                fSrcToDst[12];
+    float                fSrcToDst[16];
 
     // May contain pointers into storage or pointers into precomputed tables.
     const uint8_t*       fDstGammaTables[3];