AndroidVideoCapturerJni: Fix threading issues

webrtc/common_video/interface/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 91 matching lines @@
   void* native_handle() const override;
 
  protected:
   void* native_handle_;
   const int width_;
   const int height_;
 };
 
 class WrappedI420Buffer : public webrtc::VideoFrameBuffer {
  public:
-  WrappedI420Buffer(int desired_width,
-                    int desired_height,
-                    int width,
+  WrappedI420Buffer(int width,
                     int height,
                     const uint8_t* y_plane,
                     int y_stride,
                     const uint8_t* u_plane,
                     int u_stride,
                     const uint8_t* v_plane,
                     int v_stride,
                     const rtc::Callback0<void>& no_longer_used);
   int width() const override;
   int height() const override;
 
   const uint8_t* data(PlaneType type) const override;
   uint8_t* data(PlaneType type) override;
 
   int stride(PlaneType type) const override;
   void* native_handle() const override;
 
   rtc::scoped_refptr<VideoFrameBuffer> NativeToI420Buffer() override;
 
  private:
   friend class rtc::RefCountedObject<WrappedI420Buffer>;
   ~WrappedI420Buffer() override;
 
-  int width_;
-  int height_;
-  const uint8_t* y_plane_;
-  const uint8_t* u_plane_;
-  const uint8_t* v_plane_;
+  const int width_;
+  const int height_;
+  const uint8_t* const y_plane_;
+  const uint8_t* const u_plane_;
+  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_;
 };
 
+// Helper function to crop |buffer| without making a deep copy. May only be used
+// for non-native frames.
+rtc::scoped_refptr<VideoFrameBuffer> ShallowCenterCrop(
+    const rtc::scoped_refptr<VideoFrameBuffer>& buffer,
+    int cropped_width,
+    int cropped_height);
+
 }  // namespace webrtc
 
 #endif  // WEBRTC_VIDEO_FRAME_BUFFER_H_