Make DefaultDeleter for Video{De|En}codeAccelerator

media/video/video_decode_accelerator.h

 // Copyright (c) 2012 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 MEDIA_VIDEO_VIDEO_DECODE_ACCELERATOR_H_
 #define MEDIA_VIDEO_VIDEO_DECODE_ACCELERATOR_H_
 
 #include <vector>
 
 #include "base/basictypes.h"
 #include "media/base/bitstream_buffer.h"
 #include "media/base/video_decoder_config.h"
 #include "media/video/picture.h"
 #include "ui/gfx/size.h"
 
 namespace media {
 
 // Video decoder interface.
 // This interface is extended by the various components that ultimately
 // implement the backend of PPB_VideoDecode_Dev.
 class MEDIA_EXPORT VideoDecodeAccelerator {
  public:
-  virtual ~VideoDecodeAccelerator();
-
   // Enumeration of potential errors generated by the API.
   // Note: Keep these in sync with PP_VideoDecodeError_Dev. Also do not
   // rearrange, reuse or remove values as they are used for gathering UMA
   // statistics.
   enum Error {
     // An operation was attempted during an incompatible decoder state.
     ILLEGAL_STATE = 1,
     // Invalid argument was passed to an API method.
     INVALID_ARGUMENT,
     // Encoded input is unreadable.
@@ skipping 91 matching lines @@
   // NotifyResetDone() being called on the client.  Can be used to implement
   // "seek".
   virtual void Reset() = 0;
 
   // Destroys the decoder: all pending inputs are dropped immediately and the
   // component is freed.  This call may asynchornously free system resources,
   // but its client-visible effects are synchronous.  After this method returns
   // no more callbacks will be made on the client.  Deletes |this|
   // unconditionally, so make sure to drop all pointers to it!
   virtual void Destroy() = 0;
+
+ protected:
+  // Do not delete directly; use Destroy() or own it with a scoped_ptr, which
+  // will Destroy() it properly by default.
+  virtual ~VideoDecodeAccelerator();
 };
 
 }  // namespace media
 
+namespace base {
+
+template <class T>
+struct DefaultDeleter;
+
+// Specialize DefaultDeleter so that scoped_ptr<VideoDecodeAccelerator> always
+// uses "Destroy()" instead of trying to use the destructor.
+template <>
+struct MEDIA_EXPORT DefaultDeleter<media::VideoDecodeAccelerator> {
+ public:
+  void operator()(void* video_decode_accelerator) const;
+};
+
+}  // namespace base
+
 #endif  // MEDIA_VIDEO_VIDEO_DECODE_ACCELERATOR_H_