Maintain global lists of animation controllers

cc/animation_registrar.h

Index: cc/animation_registrar.h
diff --git a/cc/animation_registrar.h b/cc/animation_registrar.h
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+// Copyright 2012 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 CC_ANIMATION_REGISTRAR_H_
+#define CC_ANIMATION_REGISTRAR_H_
+
+#include "base/hash_tables.h"
+#include "cc/cc_export.h"
+
+namespace cc {
+  class LayerAnimationController;
+}  // namespace cc
+
+#if defined(COMPILER_GCC)
+namespace BASE_HASH_NAMESPACE {
+template<>
+struct hash<cc::LayerAnimationController*> {
+  size_t operator()(cc::LayerAnimationController* ptr) const {
+    return hash<size_t>()(reinterpret_cast<size_t>(ptr));
+  }
+};
+} // namespace BASE_HASH_NAMESPACE
+#endif // COMPILER
+
+namespace cc {
+
+class CC_EXPORT AnimationRegistrar {
+ public:
+  typedef base::hash_set<LayerAnimationController*> AnimationControllerSet;
+
+  enum ThreadName { MainThread, CompositorThread };
+
+  // Registers the given animation controller as active. An active animation
+  // controller is one that has a running animation that needs to be ticked.
+  static void ActivateAnimationController(LayerAnimationController*,
+                                          ThreadName);
+
+  // Unregisters the given animation controller. When this happens, the
+  // animation controller will no longer be ticked (since it's not active). It
+  // is not an error to call this function with a deactivated controller.
+  static void DeactivateAnimationController(LayerAnimationController*,
+                                            ThreadName);
+
+  // Gets the list of active animations for the given thread.
+  static const AnimationControllerSet& GetActiveControllers(ThreadName);
+};
+
+}  // namespace cc
+
+#endif  // CC_ANIMATION_REGISTRAR_H_