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diff --git a/third_party/chromium/base/callback_helpers.h b/third_party/chromium/base/callback_helpers.h
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+// Copyright (c) 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.
+
+// This defines helpful methods for dealing with Callbacks.  Because Callbacks
+// are implemented using templates, with a class per callback signature, adding
+// methods to Callback<> itself is unattractive (lots of extra code gets
+// generated).  Instead, consider adding methods here.
+//
+// ResetAndReturn(&cb) is like cb.Reset() but allows executing a callback (via a
+// copy) after the original callback is Reset().  This can be handy if Run()
+// reads/writes the variable holding the Callback.
+
+#ifndef BASE_CALLBACK_HELPERS_H_
+#define BASE_CALLBACK_HELPERS_H_
+
+#include "base/callback.h"
+#include "base/compiler_specific.h"
+#include "base/macros.h"
+
+namespace base {
+
+template <typename Sig>
+base::Callback<Sig> ResetAndReturn(base::Callback<Sig>* cb) {
+  base::Callback<Sig> ret(*cb);
+  cb->Reset();
+  return ret;
+}
+
+// ScopedClosureRunner is akin to std::unique_ptr<> for Closures. It ensures
+// that the Closure is executed no matter how the current scope exits.
+class BASE_EXPORT ScopedClosureRunner {
+ public:
+  ScopedClosureRunner();
+  explicit ScopedClosureRunner(const Closure& closure);
+  ~ScopedClosureRunner();
+
+  ScopedClosureRunner(ScopedClosureRunner&& other);
+
+  // Releases the current closure if it's set and replaces it with the closure
+  // from |other|.
+  ScopedClosureRunner& operator=(ScopedClosureRunner&& other);
+
+  // Calls the current closure and resets it, so it wont be called again.
+  void RunAndReset();
+
+  // Replaces closure with the new one releasing the old one without calling it.
+  void ReplaceClosure(const Closure& closure);
+
+  // Releases the Closure without calling.
+  Closure Release() WARN_UNUSED_RESULT;
+
+ private:
+  Closure closure_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedClosureRunner);
+};
+
+}  // namespace base
+
+#endif  // BASE_CALLBACK_HELPERS_H_