Introduce ViewRoot to forward input/view events to native

ui/android/ui_android_jni_registrar.cc

Index: ui/android/ui_android_jni_registrar.cc
diff --git a/ui/android/ui_android_jni_registrar.cc b/ui/android/ui_android_jni_registrar.cc
index 3c02c501c0b05ab367ee1ea4750ef5006e153bd2..7c0e014932c2f3771a888bee0cf2a4165a600b10 100644
--- a/ui/android/ui_android_jni_registrar.cc
+++ b/ui/android/ui_android_jni_registrar.cc
@@ -7,6 +7,7 @@
 #include "base/android/jni_android.h"
 #include "base/android/jni_registrar.h"
 #include "base/macros.h"
+#include "ui/android/event_handler.h"
 #include "ui/android/resources/resource_manager_impl.h"
 #include "ui/android/screen_android.h"
 #include "ui/android/view_android.h"
@@ -16,6 +17,7 @@ namespace ui {
 
 static base::android::RegistrationMethod kAndroidRegisteredMethods[] = {
     {"DisplayAndroidManager", ui::RegisterScreenAndroid},
+    {"EventHandler", ui::RegisterEventHandler},
     {"ResourceManager", ui::ResourceManagerImpl::RegisterResourceManager},
     {"WindowAndroid", WindowAndroid::RegisterWindowAndroid},
 };