Remove some unnecessary heap allocations and copies.

chrome/browser/devtools/devtools_targets_ui.h

 // Copyright 2013 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_DEVTOOLS_DEVTOOLS_TARGETS_UI_H_
 #define CHROME_BROWSER_DEVTOOLS_DEVTOOLS_TARGETS_UI_H_
 
 #include <map>
 #include <string>
 
 #include "base/callback.h"
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/devtools/device/port_forwarding_controller.h"
 
 namespace base {
 class ListValue;
 class DictionaryValue;
 }
 
 class DevToolsTargetImpl;
 class Profile;
 
 class DevToolsTargetsUIHandler {
  public:
   typedef base::Callback<void(const std::string&,
-                              scoped_ptr<base::ListValue>)> Callback;
+                              const base::ListValue&)> Callback;
   typedef base::Callback<void(DevToolsTargetImpl*)> TargetCallback;
 
-  DevToolsTargetsUIHandler(const std::string& source_id, Callback callback);
+  DevToolsTargetsUIHandler(const std::string& source_id,
+                           const Callback& callback);
   virtual ~DevToolsTargetsUIHandler();
 
   std::string source_id() const { return source_id_; }
 
   static scoped_ptr<DevToolsTargetsUIHandler> CreateForRenderers(
-      Callback callback);
+      const Callback& callback);
 
   static scoped_ptr<DevToolsTargetsUIHandler> CreateForWorkers(
-      Callback callback);
+      const Callback& callback);
 
   static scoped_ptr<DevToolsTargetsUIHandler> CreateForAdb(
-      Callback callback, Profile* profile);
+      const Callback& callback, Profile* profile);
 
   DevToolsTargetImpl* GetTarget(const std::string& target_id);
 
   virtual void Open(const std::string& browser_id, const std::string& url,
                     const TargetCallback& callback);
 
   virtual scoped_refptr<content::DevToolsAgentHost> GetBrowserAgentHost(
       const std::string& browser_id);
 
  protected:
   base::DictionaryValue* Serialize(const DevToolsTargetImpl& target);
-  void SendSerializedTargets(scoped_ptr<base::ListValue> list);
+  void SendSerializedTargets(const base::ListValue& list);
 
   typedef std::map<std::string, DevToolsTargetImpl*> TargetMap;
   TargetMap targets_;
 
  private:
   const std::string source_id_;
   Callback callback_;
 
   DISALLOW_COPY_AND_ASSIGN(DevToolsTargetsUIHandler);
 };
 
 class PortForwardingStatusSerializer
     : private PortForwardingController::Listener {
  public:
   typedef base::Callback<void(const base::Value&)> Callback;
 
   PortForwardingStatusSerializer(const Callback& callback, Profile* profile);
   virtual ~PortForwardingStatusSerializer();
 
   virtual void PortStatusChanged(const DevicesStatus&) OVERRIDE;
 
  private:
   Callback callback_;
   Profile* profile_;
 };
 
 #endif  // CHROME_BROWSER_DEVTOOLS_DEVTOOLS_TARGETS_UI_H_