Take advantage of the new Pass() machinery on scoped_ptr{,_malloc}.

media/base/pipeline.h

 // Copyright (c) 2011 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.
 
 // The pipeline is the public API clients use for playing back media.  Clients
 // provide a filter collection containing the filters they want the pipeline to
 // use to render media.
 
 #ifndef MEDIA_BASE_PIPELINE_H_
 #define MEDIA_BASE_PIPELINE_H_
@@ skipping 32 matching lines @@
 };
 
 class FilterCollection;
 
 class MEDIA_EXPORT Pipeline : public base::RefCountedThreadSafe<Pipeline> {
  public:
   // Callback that executes when a network event occurrs.
   // The parameter specifies the type of event that is being signaled.
   typedef base::Callback<void(NetworkEvent)> NetworkEventCB;
 
-  // Initializes pipeline. Pipeline takes ownership of all callbacks passed
-  // into this method.
+  // Initializes pipeline.
   // |ended_callback| will be executed when the media reaches the end.
   // |error_callback_| will be executed upon an error in the pipeline.
   // |network_callback_| will be executed when there's a network event.
   virtual void Init(const PipelineStatusCB& ended_callback,
                     const PipelineStatusCB& error_callback,
                     const NetworkEventCB& network_callback) = 0;
 
   // Build a pipeline to render the given URL using the given filter collection
   // to construct a filter chain.  Returns true if successful, false otherwise
   // (i.e., pipeline already started).  Note that a return value of true
   // only indicates that the initialization process has started successfully.
   // Pipeline initialization is an inherently asynchronous process.  Clients can
   // either poll the IsInitialized() method (discouraged) or use the
   // |start_callback| as described below.
   //
   // This method is asynchronous and can execute a callback when completed.
   // If the caller provides a |start_callback|, it will be called when the
   // pipeline initialization completes.
-  virtual bool Start(FilterCollection* filter_collection,
+  virtual bool Start(scoped_ptr<FilterCollection> filter_collection,
                      const std::string& url,
                      const PipelineStatusCB& start_callback) = 0;
 
   // Asynchronously stops the pipeline and resets it to an uninitialized state.
   // If provided, |stop_callback| will be executed when the pipeline has been
   // completely torn down and reset to an uninitialized state.  It is acceptable
   // to call Start() again once the callback has finished executing.
   //
   // Stop() must be called before destroying the pipeline.  Clients can
   // determine whether Stop() must be called by checking IsRunning().
@@ skipping 90 matching lines @@
 
  protected:
   // Only allow ourselves to be deleted by reference counting.
   friend class base::RefCountedThreadSafe<Pipeline>;
   virtual ~Pipeline() {}
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_PIPELINE_H_