compositor-worker: cc->blink mutation plumbing

third_party/WebKit/Source/platform/graphics/CompositorMutation.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CompositorMutation_h
 #define CompositorMutation_h
 
 #include "platform/graphics/CompositorMutableProperties.h"
+#include "public/platform/WebCompositorMutations.h"
 #include "third_party/skia/include/utils/SkMatrix44.h"
 #include "wtf/HashMap.h"
 
 namespace blink {
 
 class CompositorMutation {
 public:
     void setOpacity(float opacity)
     {
         m_mutatedFlags |= CompositorMutableProperty::kOpacity;
@@ skipping 26 matching lines @@
     SkMatrix44 transform() const { return m_transform; }
 
 private:
     uint32_t m_mutatedFlags = 0;
     float m_opacity = 0;
     float m_scrollLeft = 0;
     float m_scrollTop = 0;
     SkMatrix44 m_transform;
 };
 
-struct CompositorMutations {
+struct CompositorMutations : public WebCompositorMutations {

[jbroman, 2016/01/23 23:55:09]

I'd kind of like this to explicitly override the destructor:

~CompositorMutations() override {}

if only because I keep going to the base classes to check whether the HashMap
will be destroyed properly.

[majidvp, 2016/01/25 20:40:11]

Done.

     HashMap<uint64_t, OwnPtr<CompositorMutation>> map;
 };
 
 } // namespace blink
 
 #endif // CompositorMutation_h