Add initial support for NV_path_rendering extension to gpu command buffer

gpu/command_buffer/service/gles2_cmd_validation_autogen.h

Index: gpu/command_buffer/service/gles2_cmd_validation_autogen.h
diff --git a/gpu/command_buffer/service/gles2_cmd_validation_autogen.h b/gpu/command_buffer/service/gles2_cmd_validation_autogen.h
index cbdf48f79ae30356b42beab924c28792c60ff053..82418981f88901d60f2483707f41de7c93b6527a 100644
--- a/gpu/command_buffer/service/gles2_cmd_validation_autogen.h
+++ b/gpu/command_buffer/service/gles2_cmd_validation_autogen.h
@@ -33,6 +33,7 @@ ValueValidator<GLenum> get_tex_param_target;
 ValueValidator<GLenum> hint_mode;
 ValueValidator<GLenum> hint_target;
 ValueValidator<GLenum> index_type;
+ValueValidator<GLenum> matrix_mode;
 ValueValidator<GLenum> pixel_store;
 ValueValidator<GLint> pixel_store_alignment;
 ValueValidator<GLenum> pixel_type;