jni: Pass method parameters as JavaParamRef in content.

content/browser/android/web_contents_observer_proxy.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 CONTENT_BROWSER_ANDROID_WEB_CONTENTS_OBSERVER_PROXY_H_
 #define CONTENT_BROWSER_ANDROID_WEB_CONTENTS_OBSERVER_PROXY_H_
 
 #include <jni.h>
 
 #include "base/android/jni_weak_ref.h"
 #include "base/basictypes.h"
 #include "base/process/kill.h"
 #include "content/browser/web_contents/web_contents_impl.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/common/frame_navigate_params.h"
 #include "url/gurl.h"
 
 namespace content {
 
 class RenderViewHost;
 class WebContents;
 
 // Extends WebContentsObserver for providing a public Java API for some of the
 // the calls it receives.
 class WebContentsObserverProxy : public WebContentsObserver {
  public:
   WebContentsObserverProxy(JNIEnv* env, jobject obj, WebContents* web_contents);
   ~WebContentsObserverProxy() override;
 
-  void Destroy(JNIEnv* env, jobject obj);
+  void Destroy(JNIEnv* env, const base::android::JavaParamRef<jobject>& obj);
 
  private:
   void RenderViewReady() override;
   void RenderProcessGone(base::TerminationStatus termination_status) override;
   void DidStartLoading() override;
   void DidStopLoading() override;
   void DidFailProvisionalLoad(RenderFrameHost* render_frame_host,
                               const GURL& validated_url,
                               int error_code,
                               const base::string16& error_description,
@@ skipping 43 matching lines @@
 
   base::android::ScopedJavaGlobalRef<jobject> java_observer_;
 
   DISALLOW_COPY_AND_ASSIGN(WebContentsObserverProxy);
 };
 
 bool RegisterWebContentsObserverProxy(JNIEnv* env);
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_ANDROID_WEB_CONTENTS_OBSERVER_PROXY_H_