Adjust the alpha type for pixelRefs.

include/core/SkImageInfo.h

Index: include/core/SkImageInfo.h
diff --git a/include/core/SkImageInfo.h b/include/core/SkImageInfo.h
index b955433329579d6907da98a085e8b72759818fdf..174d505ae0bece977757df594deee59e4602e1bd 100644
--- a/include/core/SkImageInfo.h
+++ b/include/core/SkImageInfo.h
@@ -120,6 +120,15 @@ static inline bool SkColorTypeIsValid(unsigned value) {
 ///////////////////////////////////////////////////////////////////////////////
 
 /**
+ *  Return true if alphaType is supported by colorType. If there is a canonical

[scroggo, 2014/06/18 17:45:43]

Let me know if you think there is a better way to express this. It appears we
only return false if someone paired kIgnore_SkAlphaType (which may be going
away, IIUC?) with a valid SkColorType, or if they used an invalid SkColorType.

[reed1, 2014/06/18 17:58:20]

Good question. It would be prettier if this guy just returned a (new) alphatype.
For now leave it this way I guess, but we should keep our eyes open for the
chance to change it.

+ *  alphaType for this colorType, return it in canonical.
+ */
+bool SkValidateAlphaType(SkColorType colorType, SkAlphaType alphaType,

[reed1, 2014/06/18 17:58:20]

Wonder if the the name should start with colortype or alphatype, as the others
do...

SkColorTypeValidateAlphaType(ct, at, *at) ?

[scroggo, 2014/06/30 22:03:58]

Done.

+                         SkAlphaType* canonical = NULL);
+
+///////////////////////////////////////////////////////////////////////////////
+
+/**
  *  Describe an image's dimensions and pixel type.
  */
 struct SkImageInfo {