Pass JavaRef to Java methods in android_webview.

android_webview/native/aw_contents_background_thread_client.h

 // 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.
 
 #ifndef ANDROID_WEBVIEW_NATIVE_AW_CONTENTS_BACKGROUND_THREAD_CLIENT_H_
 #define ANDROID_WEBVIEW_NATIVE_AW_CONTENTS_BACKGROUND_THREAD_CLIENT_H_
 
 #include "base/android/scoped_java_ref.h"
 
 namespace android_webview {
 
 class AwContentsBackgroundThreadClient {
  public:
   static base::android::ScopedJavaLocalRef<jobject> shouldInterceptRequest(
       JNIEnv* env,
-      jobject obj,
-      jstring url,
+      const base::android::JavaRef<jobject>& obj,
+      const base::android::JavaRef<jstring>& url,
       jboolean isMainFrame,
       jboolean hasUserGesture,
-      jstring method,
-      jobjectArray requestHeaderNames,
-      jobjectArray requestHeaderValues);
+      const base::android::JavaRef<jstring>& method,
+      const base::android::JavaRef<jobjectArray>& requestHeaderNames,
+      const base::android::JavaRef<jobjectArray>& requestHeaderValues);
 };
 
 }
 
 #endif  // ANDROID_WEBVIEW_NATIVE_AW_CONTENTS_BACKGROUND_THREAD_CLIENT_H_