jni: Pass method parameters as JavaParamRef in chrome/browser/ui.

chrome/browser/ui/android/tab_model/tab_model_jni_bridge.h

 // Copyright 2014 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 CHROME_BROWSER_UI_ANDROID_TAB_MODEL_TAB_MODEL_JNI_BRIDGE_H_
 #define CHROME_BROWSER_UI_ANDROID_TAB_MODEL_TAB_MODEL_JNI_BRIDGE_H_
 
 #include <jni.h>
 #include <vector>
 
 #include "base/android/jni_weak_ref.h"
 #include "base/android/scoped_java_ref.h"
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 #include "chrome/browser/ui/android/tab_model/tab_model.h"
 
 class Profile;
 class TabAndroid;
 
 namespace content {
 class WebContents;
 }
 
 // Bridges calls between the C++ and the Java TabModels. Functions in this
 // class should do little more than make calls out to the Java TabModel, which
 // is what actually stores Tabs.
 class TabModelJniBridge : public TabModel {
  public:
   TabModelJniBridge(JNIEnv* env, jobject obj, bool is_incognito);
-  void Destroy(JNIEnv* env, jobject obj);
+  void Destroy(JNIEnv* env, const base::android::JavaParamRef<jobject>& obj);
   ~TabModelJniBridge() override;
 
   // Registers the JNI bindings.
   static bool Register(JNIEnv* env);
 
   // Called by JNI
-  base::android::ScopedJavaLocalRef<jobject> GetProfileAndroid(JNIEnv* env,
-                                                               jobject obj);
-  void TabAddedToModel(JNIEnv* env, jobject obj, jobject jtab);
+  base::android::ScopedJavaLocalRef<jobject> GetProfileAndroid(
+      JNIEnv* env,
+      const base::android::JavaParamRef<jobject>& obj);
+  void TabAddedToModel(JNIEnv* env,
+                       const base::android::JavaParamRef<jobject>& obj,
+                       const base::android::JavaParamRef<jobject>& jtab);
 
   // TabModel::
   int GetTabCount() const override;
   int GetActiveIndex() const override;
   content::WebContents* GetWebContentsAt(int index) const override;
   TabAndroid* GetTabAt(int index) const override;
 
   void SetActiveIndex(int index) override;
   void CloseTabAt(int index) override;
 
   void CreateTab(content::WebContents* web_contents,
                  int parent_tab_id) override;
 
   content::WebContents* CreateNewTabForDevTools(const GURL& url) override;
 
   // Return true if we are currently restoring sessions asynchronously.
   bool IsSessionRestoreInProgress() const override;
 
   // Instructs the TabModel to broadcast a notification that all tabs are now
   // loaded from storage.
-  void BroadcastSessionRestoreComplete(JNIEnv* env, jobject obj);
+  void BroadcastSessionRestoreComplete(
+      JNIEnv* env,
+      const base::android::JavaParamRef<jobject>& obj);
 
  protected:
   JavaObjectWeakGlobalRef java_object_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(TabModelJniBridge);
 };
 
 #endif  // CHROME_BROWSER_UI_ANDROID_TAB_MODEL_TAB_MODEL_JNI_BRIDGE_H_