Expand pixelref to return SkImageInfo and rowbytes

include/core/SkPixelRef.h

Index: include/core/SkPixelRef.h
diff --git a/include/core/SkPixelRef.h b/include/core/SkPixelRef.h
index d90e58719bb0b87f5bd3b5ce9b0dc4c90e056259..e3a98c579a302be2886b83e5db5496287263090f 100644
--- a/include/core/SkPixelRef.h
+++ b/include/core/SkPixelRef.h
@@ -14,6 +14,7 @@
 #include "SkRefCnt.h"
 #include "SkString.h"
 #include "SkFlattenable.h"
+#include "SkImageInfo.h"
 #include "SkTDArray.h"
 
 #ifdef SK_DEBUG
@@ -52,6 +53,11 @@ public:
     explicit SkPixelRef(SkBaseMutex* mutex = NULL);
     virtual ~SkPixelRef();
 
+    /**
+     *  Return the data's rowbytes. Will be 0 if the the lockCount is 0.
+     */
+    size_t rowBytes() const { return fRowBytes; }
+
     /** Return the pixel memory returned from lockPixels, or null if the
         lockCount is 0.
     */
@@ -231,7 +237,7 @@ protected:
     /** Called when the lockCount goes from 0 to 1. The caller will have already
         acquire a mutex for thread safety, so this method need not do that.
     */
-    virtual void* onLockPixels(SkColorTable**) = 0;
+    virtual void* onLockPixels(SkImageInfo*, size_t* rowBytes, SkColorTable**) = 0;
     /** Called when the lock count goes from 1 to 0. The caller will have
         already acquire a mutex for thread safety, so this method need not do
         that.
@@ -269,12 +275,13 @@ protected:
     // only call from constructor. Flags this to always be locked, removing
     // the need to grab the mutex and call onLockPixels/onUnlockPixels.
     // Performance tweak to avoid those calls (esp. in multi-thread use case).
-    void setPreLocked(void* pixels, SkColorTable* ctable);
+    void setPreLocked(void* pixels, size_t rowBytes, SkColorTable* ctable);
 
 private:
     SkBaseMutex*    fMutex; // must remain in scope for the life of this object
     void*           fPixels;
     SkColorTable*   fColorTable;    // we do not track ownership, subclass does
+    size_t          fRowBytes;
     int             fLockCount;
 
     mutable uint32_t fGenerationID;