Remove duplicated headers after updating downstream code.

webrtc/common_video/interface/i420_buffer_pool.h

Index: webrtc/common_video/interface/i420_buffer_pool.h
diff --git a/webrtc/common_video/interface/i420_buffer_pool.h b/webrtc/common_video/interface/i420_buffer_pool.h
deleted file mode 100644
index 37021d638321e85211a3bfa91b19e71c6373aee7..0000000000000000000000000000000000000000
--- a/webrtc/common_video/interface/i420_buffer_pool.h
+++ /dev/null
@@ -1,45 +0,0 @@
-/*
- *  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.
- */
-
-#ifndef WEBRTC_COMMON_VIDEO_INCLUDE_I420_BUFFER_POOL_H_
-#define WEBRTC_COMMON_VIDEO_INCLUDE_I420_BUFFER_POOL_H_
-
-#pragma message("WARNING: common_video/include is DEPRECATED; use common_video/include")
-
-#include <list>
-
-#include "webrtc/base/thread_checker.h"
-#include "webrtc/common_video/include/video_frame_buffer.h"
-
-namespace webrtc {
-
-// Simple buffer pool to avoid unnecessary allocations of I420Buffer objects.
-// The pool manages the memory of the I420Buffer returned from CreateBuffer.
-// When the I420Buffer is destructed, the memory is returned to the pool for use
-// by subsequent calls to CreateBuffer. If the resolution passed to CreateBuffer
-// changes, old buffers will be purged from the pool.
-class I420BufferPool {
- public:
-  I420BufferPool();
-  // Returns a buffer from the pool, or creates a new buffer if no suitable
-  // buffer exists in the pool.
-  rtc::scoped_refptr<VideoFrameBuffer> CreateBuffer(int width, int height);
-  // Clears buffers_ and detaches the thread checker so that it can be reused
-  // later from another thread.
-  void Release();
-
- private:
-  rtc::ThreadChecker thread_checker_;
-  std::list<rtc::scoped_refptr<I420Buffer>> buffers_;
-};
-
-}  // namespace webrtc
-
-#endif  // WEBRTC_COMMON_VIDEO_INCLUDE_I420_BUFFER_POOL_H_