[WIP] Add Chromium-side support for the Screen Orientation API

content/browser/screen_orientation/screen_orientation_dispatcher_host.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_SCREEN_ORIENTATION_SCREEN_ORIENTATION_DISPATCHER_HOST_H_
+#define CONTENT_BROWSER_SCREEN_ORIENTATION_SCREEN_ORIENTATION_DISPATCHER_HOST_H_
+
+#include "content/port/browser/screen_orientation_provider.h"
+#include "content/public/browser/browser_message_filter.h"
+
+namespace content {
+
+class ScreenOrientationDispatcherHost : public BrowserMessageFilter {
+ public:
+  ScreenOrientationDispatcherHost();
+ private:
+  virtual ~ScreenOrientationDispatcherHost();
+  // BrowserMessageFilter implementation.
+  virtual bool OnMessageReceived(const IPC::Message& message,
+                                 bool* message_was_ok) OVERRIDE;
+
+  void OnLockOrientation(unsigned char, bool*);

[kenneth.r.christiansen, 2014/02/06 15:03:12]

should be bool... but you might want to rethink how this could work with
promises. Ie. a promise might not fire immediately, say if the windows is
already animating something so it will have to wait a bit.

[ostap, 2014/02/06 21:23:28]

In this case I don't think sync IPC could be used. We can't block renderer
thread so long.

+  void OnUnlockOrientation();
+
+  ScreenOrientationProvider* CreateProvider();
+
+  scoped_ptr<ScreenOrientationProvider> provider_;
+  ScreenOrientationProvider::Orientations orientation_lock_;
+  DISALLOW_COPY_AND_ASSIGN(ScreenOrientationDispatcherHost);
+};
+
+}  // namespace content
+
+#endif // CONTENT_BROWSER_SCREEN_ORIENTATION_SCREEN_ORIENTATION_DISPATCHER_HOST_H_