Perform color correction on png decodes

src/core/SkColorSpaceXform.h

Index: src/core/SkColorSpaceXform.h
diff --git a/src/core/SkColorSpaceXform.h b/src/core/SkColorSpaceXform.h
index 2696b8582accdca6352fe7c5ef70d4b925e702ed..d0a46e38626e4cf980a13899724c01bbd4595e3b 100644
--- a/src/core/SkColorSpaceXform.h
+++ b/src/core/SkColorSpaceXform.h
@@ -10,6 +10,7 @@
 
 #include "SkColorSpace.h"
 #include "SkColorSpace_Base.h"
+#include "SkImageInfo.h"
 
 class SkColorSpaceXform : SkNoncopyable {
 public:
@@ -30,12 +31,17 @@ public:
 
     /**
      *  Apply the color conversion to a src buffer, storing the output in the dst buffer.
-     *  The src is stored as RGBA (8888) and is treated as opaque.
-     *  TODO (msarett): Support non-opaque srcs.
+     *  The src is stored as RGBA (8888).  If Premul is requested, the output will be
+     *  premultiplied by alpha.
      */
     virtual void applyToRGBA(RGBA32* dst, const RGBA32* src, int len) const = 0;
     virtual void applyToBGRA(BGRA32* dst, const RGBA32* src, int len) const = 0;
     virtual void applyToF16(RGBAF16* dst, const RGBA32* src, int len) const = 0;
+    virtual void applyToRGBAPremul(RGBA32* dst, const RGBA32* src, int len) const = 0;
+    virtual void applyToBGRAPremul(BGRA32* dst, const RGBA32* src, int len) const = 0;
+    virtual void applyToF16Premul(RGBAF16* dst, const RGBA32* src, int len) const = 0;
+    virtual void apply(void* dst, const RGBA32* src, int len, SkColorType dstColorType,

[msarett, 2016/07/29 18:23:01]

I'm noticing that this is really the only public function we need now.  The
others can disappear and we can call directly into SkOpts.  Thoughts?

[mtklein, 2016/07/29 18:48:56]

This sounds like a good move to me.

I think that moots the typedefs too.

[msarett, 2016/07/29 20:07:51]

Done.

+                       bool premul) const  = 0;
 
     virtual ~SkColorSpaceXform() {}
 };
@@ -47,6 +53,11 @@ public:
     void applyToRGBA(RGBA32* dst, const RGBA32* src, int len) const override;
     void applyToBGRA(BGRA32* dst, const RGBA32* src, int len) const override;
     void applyToF16(RGBAF16* dst, const RGBA32* src, int len) const override;
+    void applyToRGBAPremul(RGBA32* dst, const RGBA32* src, int len) const override;
+    void applyToBGRAPremul(BGRA32* dst, const RGBA32* src, int len) const override;
+    void applyToF16Premul(RGBAF16* dst, const RGBA32* src, int len) const override;
+    void apply(void* dst, const RGBA32* src, int len, SkColorType dstColorType, bool premul)
+    const override;
 
     static constexpr int      kDstGammaTableSize = 1024;