compositor-worker: cc->blink mutation plumbing

third_party/WebKit/public/platform/WebCompositorMutations.h

Index: third_party/WebKit/public/platform/WebCompositorMutations.h
diff --git a/third_party/WebKit/public/platform/WebCompositorMutations.h b/third_party/WebKit/public/platform/WebCompositorMutations.h
new file mode 100644
index 0000000000000000000000000000000000000000..d0d7e1c8bea3aae94ba4775fc0927ac8aff67d7a
--- /dev/null
+++ b/third_party/WebKit/public/platform/WebCompositorMutations.h
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+// 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 WebCompositorMutations_h
+#define WebCompositorMutations_h
+
+#include "cc/animation/layer_tree_mutations.h"
+
+namespace blink {
+
+// This class contains the mutation data to be plumbed back to the main thread
+// after a CompositorWorker callback runs. It is a do-nothing base class since
+// these mutations are only used within blink.
+struct WebCompositorMutations : public cc::LayerTreeMutations {
+    ~WebCompositorMutations() override { }
+};
+
+} // namespace blink
+
+#endif // WebCompositorMutations_h