jni_generator: Pass object parameters as JavaParamRef.

chrome/browser/android/compositor/scene_layer/scene_layer.cc

 // Copyright 2015 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.
 
 #include "chrome/browser/android/compositor/scene_layer/scene_layer.h"
 
 #include "cc/layers/layer.h"
 #include "content/public/browser/android/compositor.h"
 #include "jni/SceneLayer_jni.h"
 
@@ skipping 40 matching lines @@
 }
 
 bool SceneLayer::ShouldShowBackground() {
   return false;
 }
 
 SkColor SceneLayer::GetBackgroundColor() {
   return SK_ColorWHITE;
 }
 
-static jlong Init(JNIEnv* env, jobject jobj) {
+static jlong Init(JNIEnv* env, const JavaParamRef<jobject>& jobj) {
   // This will automatically bind to the Java object and pass ownership there.
   SceneLayer* tree_provider = new SceneLayer(env, jobj);
   return reinterpret_cast<intptr_t>(tree_provider);
 }
 
 bool RegisterSceneLayer(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 }  // namespace android
 }  // namespace chrome