Support Float32 output from SkColorSpaceXform

src/codec/SkPngCodec.h

Index: src/codec/SkPngCodec.h
diff --git a/src/codec/SkPngCodec.h b/src/codec/SkPngCodec.h
index e3059ba0d55422b4442a3e4a1e42bedecef3453a..1fc451757eef4dcafb7bf5586d69a5800b3d5cac 100644
--- a/src/codec/SkPngCodec.h
+++ b/src/codec/SkPngCodec.h
@@ -64,7 +64,7 @@ protected:
     SkSwizzler* swizzler() { return fSwizzler; }
 
     // Initialize variables used by applyXformRow.
-    void initializeXformAlphaAndWidth();
+    void initializeXformParams();
 
     /**
      *  Pass available input to libpng to process it.
@@ -128,9 +128,10 @@ private:
     virtual void setRange(int firstRow, int lastRow, void* dst, size_t rowBytes) = 0;
     virtual Result decode(int* rowsDecoded) = 0;
 
-    XformMode   fXformMode;
-    SkAlphaType fXformAlphaType;
-    int         fXformWidth;
+    XformMode                      fXformMode;
+    SkColorSpaceXform::ColorFormat fXformColorFormat;
+    SkAlphaType                    fXformAlphaType;
+    int                            fXformWidth;
 
 #ifdef SK_GOOGLE3_PNG_HACK
     bool        fNeedsToRereadHeader;