[PresentationAPI, Android] Add ChromeMediaRouter.java and bind it with the native MediaRouterAndroid

chrome/browser/media/android/router/media_router_android.h

Index: chrome/browser/media/android/router/media_router_android.h
diff --git a/chrome/browser/media/android/router/media_router_android.h b/chrome/browser/media/android/router/media_router_android.h
index eb14600317b6b11351472d6e9a1e71c39ba798e3..bc6e4c43ae567ecc752c6a056f6eb8a5c92e5ec5 100644
--- a/chrome/browser/media/android/router/media_router_android.h
+++ b/chrome/browser/media/android/router/media_router_android.h
@@ -5,6 +5,9 @@
 #ifndef CHROME_BROWSER_MEDIA_ANDROID_ROUTER_MEDIA_ROUTER_ANDROID_H_
 #define CHROME_BROWSER_MEDIA_ANDROID_ROUTER_MEDIA_ROUTER_ANDROID_H_
 
+#include <jni.h>
+
+#include "base/android/scoped_java_ref.h"
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/media/router/media_router.h"
 
@@ -19,6 +22,8 @@ class MediaRouterAndroid : public MediaRouter {
  public:
   ~MediaRouterAndroid() override;
 
+  static bool Register(JNIEnv* env);
+
   // MediaRouter implementation.
   void CreateRoute(
       const MediaSource::Id& source_id,
@@ -59,6 +64,8 @@ class MediaRouterAndroid : public MediaRouter {
   void UnregisterPresentationSessionMessagesObserver(
       PresentationSessionMessagesObserver* observer) override;
 
+  base::android::ScopedJavaGlobalRef<jobject> java_media_router_;
+
   DISALLOW_COPY_AND_ASSIGN(MediaRouterAndroid);
 };