Add YUV_420_BIPLANAR to gfx::BufferFormat.

ui/gfx/buffer_format_util.cc

 // Copyright 2015 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.
 
 #include "ui/gfx/buffer_format_util.h"
 
 #include "base/logging.h"
 
 namespace gfx {
 
 size_t NumberOfPlanesForBufferFormat(BufferFormat format) {
   switch (format) {
     case BufferFormat::ATC:
     case BufferFormat::ATCIA:
     case BufferFormat::DXT1:
     case BufferFormat::DXT5:
     case BufferFormat::ETC1:
     case BufferFormat::R_8:
     case BufferFormat::RGBA_4444:
     case BufferFormat::RGBA_8888:
     case BufferFormat::RGBX_8888:
     case BufferFormat::BGRA_8888:
       return 1;
+    case BufferFormat::YUV_420_BIPLANAR:
+      return 2;
     case BufferFormat::YUV_420:
       return 3;
   }
   NOTREACHED();
   return 0;
 }
 
 }  // namespace gfx