Centralize ScreenOrientationProvider logic, add platform delegates

content/browser/screen_orientation/screen_orientation_delegate_android.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_DELEGATE_H_
+#define CONTENT_BROWSER_SCREEN_ORIENTATION_SCREEN_ORIENTATION_DELEGATE_H_
+
+#include <jni.h>
+
+#include "base/macros.h"
+#include "content/public/browser/screen_orientation_delegate.h"
+#include "third_party/WebKit/public/platform/WebScreenOrientationLockType.h"
+
+namespace content {
+
+class WebContents;
+
+// Android implementation of ScreenOrientationDelegate. The functionality of
+// ScreenOrientationProvider is always supported.
+class ScreenOrientationDelegateAndroid : public ScreenOrientationDelegate {
+ public:
+  ScreenOrientationDelegateAndroid();
+  virtual ~ScreenOrientationDelegateAndroid();
+
+  static bool Register(JNIEnv* env);
+
+  // Ask the ScreenOrientationListener (Java) to start accurately listening to
+  // the screen orientation. It keep track of the number of start request if it
+  // is already running an accurate listening.
+  static void StartAccurateListening();
+
+  // Ask the ScreenOrientationListener (Java) to stop accurately listening to
+  // the screen orientation. It will actually stop only if the number of stop
+  // requests matches the number of start requests.
+  static void StopAccurateListening();
+
+  // ScreenOrientationDelegate:
+  virtual bool FullScreenRequired(WebContents* web_contents) OVERRIDE;
+  virtual void Lock(
+      blink::WebScreenOrientationLockType lock_orientation) OVERRIDE;
+  virtual bool ScreenOrientationProviderSupported() OVERRIDE;
+  virtual void Unlock() OVERRIDE;
+
+ private:
+  DISALLOW_COPY_AND_ASSIGN(ScreenOrientationDelegateAndroid);
+};
+
+} // namespace content
+
+#endif // CONTENT_BROWSER_SCREEN_ORIENTATION_SCREEN_ORIENTATION_DELEGATE_H_