Revert of remvoe duplicate impl for SkImageInfo flattening

include/gpu/SkGrPixelRef.h

Index: include/gpu/SkGrPixelRef.h
diff --git a/include/gpu/SkGrPixelRef.h b/include/gpu/SkGrPixelRef.h
index 4d33b9d06b01498e9891db2e3dd2b43bd414016b..c29c27fb3bdc0b3d0963fcaa0fda82ef3d0285a1 100644
--- a/include/gpu/SkGrPixelRef.h
+++ b/include/gpu/SkGrPixelRef.h
@@ -23,13 +23,14 @@
  */
 class SK_API SkROLockPixelsPixelRef : public SkPixelRef {
 public:
-    SkROLockPixelsPixelRef(const SkImageInfo&);
+    SkROLockPixelsPixelRef();
     virtual ~SkROLockPixelsPixelRef();
 
 protected:
-    virtual bool onNewLockPixels(LockRec*) SK_OVERRIDE;
-    virtual void onUnlockPixels() SK_OVERRIDE;
-    virtual bool onLockPixelsAreWritable() const SK_OVERRIDE;   // return false;
+    // override from SkPixelRef
+    virtual void* onLockPixels(SkColorTable** ptr);
+    virtual void onUnlockPixels();
+    virtual bool onLockPixelsAreWritable() const;   // return false;
 
 private:
     SkBitmap    fBitmap;
@@ -46,6 +47,7 @@
      * cache and would like the pixel ref to unlock it in its destructor then transferCacheLock
      * should be set to true.
      */
+    SkGrPixelRef(GrSurface*, bool transferCacheLock = false);
     SkGrPixelRef(const SkImageInfo&, GrSurface*, bool transferCacheLock = false);
     virtual ~SkGrPixelRef();