Add ExternalPrerenderRequestHandler and related API

chrome/browser/android/external_prerender_request_handler.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 CHROME_BROWSER_ANDROID_EXTERNAL_PRERENDER_REQUEST_HANDLER_H_
+#define CHROME_BROWSER_ANDROID_EXTERNAL_PRERENDER_REQUEST_HANDLER_H_
+
+#include <jni.h>
+
+#include "base/android/scoped_java_ref.h"
+#include "base/memory/ref_counted.h"
+#include "base/memory/scoped_ptr.h"
+
+namespace prerender {
+class PrerenderHandle;
+class PrerenderManager;
+}
+
+//
+class ExternalPrerenderRequestHandler {
+ public:
+  int AddPrerender(JNIEnv* env,
+                       jobject obj,
+                       jstring url,
+                       jstring referrer,
+                       jint width,
+                       jint height);
+  static bool RegisterExternalPrerenderRequestHandler(JNIEnv* env);
+
+  explicit ExternalPrerenderRequestHandler();
+  virtual ~ExternalPrerenderRequestHandler();
+
+ private:
+  prerender::PrerenderManager* GetPrerenderManager() const;
+
+  scoped_ptr<prerender::PrerenderHandle> prerender_handle_;
+};
+
+#endif  // CHROME_BROWSER_ANDROID_EXTERNAL_PRERENDER_REQUEST_HANDLER_H_