compositor-worker: plumb element id and mutable properties

third_party/WebKit/public/platform/WebCompositorMutableProperties.h

Index: third_party/WebKit/public/platform/WebCompositorMutableProperties.h
diff --git a/third_party/WebKit/public/platform/WebCompositorMutableProperties.h b/third_party/WebKit/public/platform/WebCompositorMutableProperties.h
new file mode 100644
index 0000000000000000000000000000000000000000..63b37973bb7a388aac0b5b0d38a190e8fafb845e
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+++ b/third_party/WebKit/public/platform/WebCompositorMutableProperties.h
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+// Copyright 2015 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 WebCompositorMutableProperties_h
+#define WebCompositorMutableProperties_h
+
+namespace blink {
+
+// TODO(vollick): we should not need a parallel enum. This must be kept in sync
+// with the cc::MutableProperty enum.
+enum WebCompositorMutableProperty {
+    WebCompositorMutablePropertyNone = 0,
+    WebCompositorMutablePropertyOpacity = 1 << 0,
+    WebCompositorMutablePropertyScrollLeft = 1 << 1,
+    WebCompositorMutablePropertyScrollTop = 1 << 2,
+    WebCompositorMutablePropertyTransform = 1 << 3,
+};
+
+const int kNumWebCompositorMutableProperties = 4;
+
+} // namespace blink
+
+#endif // WebCompositorMutableProperties_h