jni_generator: Pass object parameters as JavaParamRef.

ui/android/window_android.cc

Index: ui/android/window_android.cc
diff --git a/ui/android/window_android.cc b/ui/android/window_android.cc
index 0106ba1829895a6e97f9c48e7d71b50c784ba35f..5fe7779a2716b142c9818f9a3b8dde01d9d0cd9e 100644
--- a/ui/android/window_android.cc
+++ b/ui/android/window_android.cc
@@ -136,7 +136,7 @@ bool WindowAndroid::CanRequestPermission(const std::string& permission) {
 // Native JNI methods
 // ----------------------------------------------------------------------------
 
-jlong Init(JNIEnv* env, jobject obj) {
+jlong Init(JNIEnv* env, const JavaParamRef<jobject>& obj) {
   WindowAndroid* window = new WindowAndroid(env, obj);
   return reinterpret_cast<intptr_t>(window);
 }