gpu: Add YCbCr 420v extension.

gpu/GLES2/gl2extchromium.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.
 
 // This file contains Chromium-specific GLES2 extensions declarations.
 
 #ifndef GPU_GLES2_GL2EXTCHROMIUM_H_
 #define GPU_GLES2_GL2EXTCHROMIUM_H_
 
 #include <GLES2/gl2.h>
@@ skipping 109 matching lines @@
 #endif
 
 #ifndef GL_RGB_YUV_420_CHROMIUM
 #define GL_RGB_YUV_420_CHROMIUM 0x78FA
 #endif
 
 #ifndef GL_RGB_YCBCR_422_CHROMIUM
 #define GL_RGB_YCBCR_422_CHROMIUM 0x78FB
 #endif
 
+#ifndef GL_RGB_YCBCR_420V_CHROMIUM
+#define GL_RGB_YCBCR_420V_CHROMIUM 0x78FC
+#endif
+
 #ifdef GL_GLEXT_PROTOTYPES
 GL_APICALL GLuint GL_APIENTRY glCreateGpuMemoryBufferImageCHROMIUM(
     GLsizei width,
     GLsizei height,
     GLenum internalformat,
     GLenum usage);
 #endif
 typedef GLuint(GL_APIENTRYP PFNGLCREATEGPUMEMORYBUFFERIMAGECHROMIUMPROC)(
     GLsizei width,
     GLsizei height,
@@ skipping 842 matching lines @@
 #define GL_PATH_STENCIL_VALUE_MASK_CHROMIUM 0x90B9
 #endif
 
 #endif /* GL_CHROMIUM_path_rendering */
 
 #ifdef __cplusplus
 }
 #endif
 
 #endif  // GPU_GLES2_GL2EXTCHROMIUM_H_