Revert "Revert of https://codereview.chromium.org/110593003/"

src/lazy/SkDiscardablePixelRef.h

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkDiscardablePixelRef_DEFINED
 #define SkDiscardablePixelRef_DEFINED
 
@@ skipping 10 matching lines @@
  *  Since SkColorTable is reference-counted, we do not support indexed
  *  color with this class; there would be no way for the discardable
  *  memory system to unref the color table.
  */
 class SkDiscardablePixelRef : public SkPixelRef {
 public:
     SK_DECLARE_UNFLATTENABLE_OBJECT()
 
 protected:
     ~SkDiscardablePixelRef();
-    virtual void* onLockPixels(SkColorTable**) SK_OVERRIDE;
+
+    virtual bool onNewLockPixels(LockRec*) SK_OVERRIDE;
     virtual void onUnlockPixels() SK_OVERRIDE;
     virtual bool onLockPixelsAreWritable() const SK_OVERRIDE { return false; }
 
     virtual SkData* onRefEncodedData() SK_OVERRIDE {
         return fGenerator->refEncodedData();
     }
 
 private:
     SkImageGenerator* const fGenerator;
     SkDiscardableMemory::Factory* const fDMFactory;
     const size_t fRowBytes;
     // These const members should not change over the life of the
     // PixelRef, since the SkBitmap doesn't expect them to change.
 
     SkDiscardableMemory* fDiscardableMemory;
 
     /* Takes ownership of SkImageGenerator. */
     SkDiscardablePixelRef(const SkImageInfo&, SkImageGenerator*,
                           size_t rowBytes,
                           SkDiscardableMemory::Factory* factory);
+
     friend bool SkInstallDiscardablePixelRef(SkImageGenerator*,
                                              SkBitmap*,
                                              SkDiscardableMemory::Factory*);
+
     typedef SkPixelRef INHERITED;
 };
+
 #endif  // SkDiscardablePixelRef_DEFINED