Add glTransformFeedbackVaryings to GPU command buffer.

gpu/command_buffer/client/gles2_interface_stub_autogen.h

Index: gpu/command_buffer/client/gles2_interface_stub_autogen.h
diff --git a/gpu/command_buffer/client/gles2_interface_stub_autogen.h b/gpu/command_buffer/client/gles2_interface_stub_autogen.h
index 76e09b1406946c356d6d42ab2461448e86cb5665..44c4c4f333515afea6f19bc958126e8f04d6f91f 100644
--- a/gpu/command_buffer/client/gles2_interface_stub_autogen.h
+++ b/gpu/command_buffer/client/gles2_interface_stub_autogen.h
@@ -357,6 +357,10 @@ void TexSubImage3D(GLenum target,
                    GLenum format,
                    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;
 void Uniform1i(GLint location, GLint x) override;