Fix CompositorResizeLock to do something.

content/browser/renderer_host/compositor_resize_lock.h

+// Copyright 2014 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 CONTENT_BROWSER_RENDERER_HOST_COMPOSITOR_RESIZE_LOCK_H_
+#define CONTENT_BROWSER_RENDERER_HOST_COMPOSITOR_RESIZE_LOCK_H_
+
+#include "base/macros.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
+#include "base/time/time.h"
+#include "ui/compositor/compositor_lock.h"
+#include "ui/gfx/geometry/size.h"
+
+namespace content {
+
+class CompositorResizeLockClient {
+ public:
+  virtual ~CompositorResizeLockClient() {}
+
+  // Creates and returns a CompositorLock for the CompositoResizeLock to
+  // hold.
+  virtual std::unique_ptr<ui::CompositorLock> GetCompositorLock(
+      ui::CompositorLockClient* client) = 0;
+
+  // Called when the CompositorResizeLock ends. This can happen
+  // before the CompositorResizeLock is destroyed if it times out.
+  virtual void CompositorResizeLockEnded() = 0;
+};
+
+// Used to prevent further resizes while a resize is pending.
+class CompositorResizeLock
+    : NON_EXPORTED_BASE(public ui::CompositorLockClient) {
+ public:
+  CompositorResizeLock(CompositorResizeLockClient* client,
+                       const gfx::Size& new_size);
+  ~CompositorResizeLock() override;
+
+  // Returns |true| if the call locks the compositor, or false if it was ever
+  // locked/unlocked.
+  bool Lock();
+
+  // Releases the lock on the compositor without releasing the whole resize
+  // lock. The client is not told about this. If called before locking, it will
+  // prevent locking from happening.
+  void UnlockCompositor();
+
+  const gfx::Size& expected_size() const { return expected_size_; }
+
+ private:
+  // ui::CompositorLockClient implementation.
+  void CompositorLockTimedOut() override;
+
+  CompositorResizeLockClient* client_;
+  const gfx::Size expected_size_;
+  std::unique_ptr<ui::CompositorLock> compositor_lock_;
+  bool unlocked_ = false;
+
+  DISALLOW_COPY_AND_ASSIGN(CompositorResizeLock);
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_RENDERER_HOST_COMPOSITOR_RESIZE_LOCK_AURA_H_