jni: Pass method parameters as JavaParamRef in content.

content/browser/android/web_contents_observer_proxy.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 "content/browser/android/web_contents_observer_proxy.h"
 
 #include <string>
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_string.h"
@@ skipping 30 matching lines @@
            const JavaParamRef<jobject>& java_web_contents) {
   WebContents* web_contents =
       WebContents::FromJavaWebContents(java_web_contents);
   CHECK(web_contents);
 
   WebContentsObserverProxy* native_observer =
       new WebContentsObserverProxy(env, obj, web_contents);
   return reinterpret_cast<intptr_t>(native_observer);
 }
 
-void WebContentsObserverProxy::Destroy(JNIEnv* env, jobject obj) {
+void WebContentsObserverProxy::Destroy(JNIEnv* env,
+                                       const JavaParamRef<jobject>& obj) {
   delete this;
 }
 
 void WebContentsObserverProxy::WebContentsDestroyed() {
   JNIEnv* env = AttachCurrentThread();
   ScopedJavaLocalRef<jobject> obj(java_observer_);
   // The java side will destroy |this|
   Java_WebContentsObserverProxy_destroy(env, obj.obj());
 }
 
@@ skipping 242 matching lines @@
       web_contents()->GetController().GetLastCommittedEntry();
   // Note that GetBaseURLForDataURL is only used by the Android WebView.
   if (entry && !entry->GetBaseURLForDataURL().is_empty())
     *url = entry->GetBaseURLForDataURL().possibly_invalid_spec();
 }
 
 bool RegisterWebContentsObserverProxy(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 }  // namespace content