1 files changed, 51 insertions, 1 deletions
diff --git a/cc/rate_limiter.h b/cc/rate_limiter.h
index 638cbb2..7b48d74 100644
--- a/cc/rate_limiter.h
+++ b/cc/rate_limiter.h
@@ -1,3 +1,53 @@
-// Copyright 2012 The Chromium Authors. All rights reserved.
+// Copyright 2011 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 RateLimiter_h
+#define RateLimiter_h
+
+#if USE(ACCELERATED_COMPOSITING)
+
+#include "base/memory/ref_counted.h"
+
+namespace WebKit {
+class WebGraphicsContext3D;
+}
+
+namespace cc {
+
+class RateLimiterClient {
+public:
+    virtual void rateLimit() = 0;
+};
+
+// A RateLimiter can be used to make sure that a single context does not dominate all execution time.
+// To use, construct a RateLimiter class around the context and call start() whenever calls are made on the
+// context outside of normal flow control. RateLimiter will block if the context is too far ahead of the
+// compositor.
+class RateLimiter : public base::RefCounted<RateLimiter> {
+public:
+    static scoped_refptr<RateLimiter> create(WebKit::WebGraphicsContext3D*, RateLimiterClient*);
+
+    void start();
+
+    // Context and client will not be accessed after stop().
+    void stop();
+
+private:
+    RateLimiter(WebKit::WebGraphicsContext3D*, RateLimiterClient*);
+    ~RateLimiter();
+    friend class base::RefCounted<RateLimiter>;
+
+    class Task;
+    friend class Task;
+    void rateLimitContext();
+
+    WebKit::WebGraphicsContext3D* m_context;
+    bool m_active;
+    RateLimiterClient *m_client;
+};
+
+}
+#endif // USE(ACCELERATED_COMPOSITING)
+
+#endif