Make VibrationMessageFilter available to other platforms.

content/browser/vibration_message_filter.h

+// Copyright 2013 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_VIBRATION_MESSAGE_FILTER_H_
+#define CONTENT_BROWSER_VIBRATION_MESSAGE_FILTER_H_
+
+#include "content/public/browser/browser_message_filter.h"
+
+namespace content {
+
+class CONTENT_EXPORT VibrationMessageFilter
+    : public BrowserMessageFilter {
+ public:
+  VibrationMessageFilter();

[Peter Beverloo, 2013/09/13 16:14:12]

If the Create() method is static, then the constructor shouldn't be public. 
Since we're not doing anything in it anyway, it's fine to remove it.

+
+  // Create instance of VibrationMessageFilter.

[Peter Beverloo, 2013/09/13 16:14:12]

"Create a platform-specific instance of the VibrationMessageFilter."

+  // Returns NULL if factory is not set (default implementation on android).
+  static VibrationMessageFilter* Create();
+
+  // Sets the VibrationMessageFilter factory function.
+  typedef VibrationMessageFilter* Factory();

[Peter Beverloo, 2013/09/13 16:14:12]

I'm not too fussed about this.  Like I asked earlier, is it for testing?  If so,
can we add it later when you actually implement tests?

+  static void SetFactory(Factory* factory);
+
+ protected:
+  // Device should start vibrating for N milliseconds.

[Peter Beverloo, 2013/09/13 16:14:12]

nit: I'd prefer it if this could be written as "vibrating for |milliseconds|
ms".

+  virtual void OnVibrate(int64 milliseconds) = 0;
+  // Cancels vibration of the device.

[Peter Beverloo, 2013/09/13 16:14:12]

nit: empty line above here, perhaps?

+  virtual void OnCancelVibration() = 0;
+
+  virtual ~VibrationMessageFilter();
+
+ private:
+  // BrowserMessageFilter implementation.
+  virtual bool OnMessageReceived(const IPC::Message& message,
+                                 bool* message_was_ok) OVERRIDE;
+
+  static Factory* factory_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_BROWSER_VIBRATION_MESSAGE_FILTER_H_