Implement scoped_const_refptr template.

webrtc/common_video/include/video_frame_buffer.h

 /*
  *  Copyright (c) 2015 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 106 matching lines @@
   uint8_t* MutableDataV() override;
   int StrideY() const override;
   int StrideU() const override;
   int StrideV() const override;
 
   void* native_handle() const override;
   rtc::scoped_refptr<VideoFrameBuffer> NativeToI420Buffer() override;
 
   // Create a new buffer and copy the pixel data.
   static rtc::scoped_refptr<I420Buffer> Copy(
-      const rtc::scoped_refptr<VideoFrameBuffer>& buffer);
+      const rtc::scoped_const_refptr<VideoFrameBuffer>& buffer);
 
   // Scale the cropped area of |src| to the size of |this| buffer, and
   // write the result into |this|.
-  void CropAndScaleFrom(const rtc::scoped_refptr<VideoFrameBuffer>& src,
+  void CropAndScaleFrom(const rtc::scoped_const_refptr<VideoFrameBuffer>& src,
                         int offset_x,
                         int offset_y,
                         int crop_width,
                         int crop_height);
 
   // The common case of a center crop, when needed to adjust the
   // aspect ratio without distorting the image.
-  void CropAndScaleFrom(const rtc::scoped_refptr<VideoFrameBuffer>& src);
+  void CropAndScaleFrom(const rtc::scoped_const_refptr<VideoFrameBuffer>& src);
 
   // Scale all of |src| to the size of |this| buffer, with no cropping.
-  void ScaleFrom(const rtc::scoped_refptr<VideoFrameBuffer>& src);
+  void ScaleFrom(const rtc::scoped_const_refptr<VideoFrameBuffer>& src);
 
   // Create a new buffer with identical strides, and copy the pixel data.
   static rtc::scoped_refptr<I420Buffer> CopyKeepStride(
-      const rtc::scoped_refptr<VideoFrameBuffer>& buffer);
+      const rtc::scoped_const_refptr<VideoFrameBuffer>& buffer);
 
  protected:
   ~I420Buffer() override;
 
  private:
   const int width_;
   const int height_;
   const int stride_y_;
   const int stride_u_;
   const int stride_v_;
@@ skipping 61 matching lines @@
   const uint8_t* const v_plane_;
   const int y_stride_;
   const int u_stride_;
   const int v_stride_;
   rtc::Callback0<void> no_longer_used_cb_;
 };
 
 }  // namespace webrtc
 
 #endif  // WEBRTC_COMMON_VIDEO_INCLUDE_VIDEO_FRAME_BUFFER_H_