Add initial support for NV_path_rendering extension to gpu command buffer

gpu/GLES2/gl2chromium.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 declarations.
 
 #ifndef GPU_GLES2_GL2CHROMIUM_H_
 #define GPU_GLES2_GL2CHROMIUM_H_
 
 #include <GLES2/gl2platform.h>
 
 #define GL_CONTEXT_LOST 0x300E
+#define GL_PATH_MODELVIEW_CHROMIUM 0x1700
+#define GL_PATH_PROJECTION_CHROMIUM 0x1701
+#define GL_PATH_MODELVIEW_MATRIX_CHROMIUM 0x0BA6
+#define GL_PATH_PROJECTION_MATRIX_CHROMIUM 0x0BA7
 
 #if defined(GLES2_USE_MOJO)
 #define GLES2_GET_FUN(name) MojoGLES2gl ## name
 #else
 // Because we are using both the real system GL and our own
 // emulated GL we need to use different names to avoid conflicts.
 #if defined(GLES2_USE_CPP_BINDINGS)
 #define GLES2_GET_FUN(name) gles2::GetGLContext()->name
 #else
 #define GLES2_GET_FUN(name) GLES2 ## name
 #endif
 #endif
 
 #include <GLES2/gl2chromium_autogen.h>
 
 #endif  // GPU_GLES2_GL2CHROMIUM_H_