Fix incorrect VideoFrame::row_bytes() for RGB. Add tests.

media/base/video_frame.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_BASE_VIDEO_FRAME_H_
 #define MEDIA_BASE_VIDEO_FRAME_H_
 
 #include "base/callback.h"
 #include "media/base/buffers.h"
 
@@ skipping 65 matching lines @@
   // Allocates YV12 frame based on |width| and |height|, and sets its data to
   // the YUV equivalent of RGB(0,0,0).
   static scoped_refptr<VideoFrame> CreateBlackFrame(int width, int height);
 
   Format format() const { return format_; }
 
   size_t width() const { return width_; }
 
   size_t height() const { return height_; }
 
-  int stride(size_t plane) const;
+  size_t stride(size_t plane) const;
 
   // Returns the number of bytes per row and number of rows for a given plane.
   //
   // As opposed to stride(), row_bytes() refers to the bytes representing
   // visible pixels.
-  int row_bytes(size_t plane) const;
-  int rows(size_t plane) const;
+  size_t row_bytes(size_t plane) const;
+  size_t rows(size_t plane) const;
 
   // Returns pointer to the buffer for a given plane. The memory is owned by
   // VideoFrame object and must not be freed by the caller.
   uint8* data(size_t plane) const;
 
   // Returns the ID of the native texture wrapped by this frame.  Only valid to
   // call if this is a NATIVE_TEXTURE frame.
   uint32 texture_id() const;
 
   // Returns the texture target. Only valid for NATIVE_TEXTURE frames.
@@ skipping 38 matching lines @@
   uint32 texture_id_;
   uint32 texture_target_;
   base::Closure texture_no_longer_needed_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(VideoFrame);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_VIDEO_FRAME_H_