Add glTransformFeedbackVaryings to GPU command buffer.

gpu/command_buffer/client/gles2_implementation_autogen.h

Index: gpu/command_buffer/client/gles2_implementation_autogen.h
diff --git a/gpu/command_buffer/client/gles2_implementation_autogen.h b/gpu/command_buffer/client/gles2_implementation_autogen.h
index 0572358065c7d07e67ee2584523934968db922ca..7722acdde7796f3ef1408cd2a6b0f1e750b0aede 100644
--- a/gpu/command_buffer/client/gles2_implementation_autogen.h
+++ b/gpu/command_buffer/client/gles2_implementation_autogen.h
@@ -497,6 +497,11 @@ void TexSubImage3D(GLenum target,
                    GLenum type,
                    const void* pixels) override;
 
+void TransformFeedbackVaryings(GLuint program,
+                               GLsizei count,
+                               const char* const* varyings,
+                               GLenum buffermode) override;
+
 void Uniform1f(GLint location, GLfloat x) override;
 
 void Uniform1fv(GLint location, GLsizei count, const GLfloat* v) override;