Make SkBitmap::CopyTo respect requested dst color type when bitmap is texture backed.

include/core/SkPixelRef.h

 /*
  * Copyright 2008 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkPixelRef_DEFINED
 #define SkPixelRef_DEFINED
 
@@ skipping 207 matching lines @@
      *  match what it expected. If the sizes do not match, it should return false.
      *
      *  If colorSpace is not NULL, the YUV color space of the data should be stored in the address
      *  it points at.
      */
     bool getYUV8Planes(SkISize sizes[3], void* planes[3], size_t rowBytes[3],
                        SkYUVColorSpace* colorSpace) {
         return this->onGetYUV8Planes(sizes, planes, rowBytes, colorSpace);
     }
 
-    bool readPixels(SkBitmap* dst, const SkIRect* subset = NULL);
+    /** Populates dst with the pixels of this pixelRef, converting them to colorType. */
+    bool readPixels(SkBitmap* dst, SkColorType colorType, const SkIRect* subset = NULL);
 
     /**
      *  Makes a deep copy of this PixelRef, respecting the requested config.
      *  @param colorType Desired colortype.
      *  @param profileType Desired colorprofiletype.
      *  @param subset Subset of this PixelRef to copy. Must be fully contained within the bounds of
      *         of this PixelRef.
      *  @return A new SkPixelRef, or NULL if either there is an error (e.g. the destination could
      *          not be created with the given config), or this PixelRef does not support deep
      *          copies.
@@ skipping 53 matching lines @@
 
     /** Default impl returns true */
     virtual bool onLockPixelsAreWritable() const;
 
     /**
      *  For pixelrefs that don't have access to their raw pixels, they may be
      *  able to make a copy of them (e.g. if the pixels are on the GPU).
      *
      *  The base class implementation returns false;
      */
-    virtual bool onReadPixels(SkBitmap* dst, const SkIRect* subsetOrNull);
+    virtual bool onReadPixels(SkBitmap* dst, SkColorType colorType, const SkIRect* subsetOrNull);
 
     // default impl returns NULL.
     virtual SkData* onRefEncodedData();
 
     // default impl does nothing.
     virtual void onNotifyPixelsChanged();
 
     // default impl returns false.
     virtual bool onGetYUV8Planes(SkISize sizes[3], void* planes[3], size_t rowBytes[3],
                                  SkYUVColorSpace* colorSpace);
@@ skipping 85 matching lines @@
     /**
      *  Allocate a new pixelref matching the specified ImageInfo, allocating
      *  the memory for the pixels. If the ImageInfo requires a ColorTable,
      *  the pixelref will ref() the colortable.
      *  On failure return NULL.
      */
     virtual SkPixelRef* create(const SkImageInfo&, size_t rowBytes, SkColorTable*) = 0;
 };
 
 #endif