var gl = wtu.create3DContext(c);
gl.clearColor(0,1,0,1);
gl.clear(gl.COLOR_BUFFER_BIT);
-wtu.waitForComposite(gl, function() {
+wtu.waitForComposite(function() {
gl.readPixels(0, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, new Uint8Array(4));
wtu.glErrorShouldBe(gl, gl.NO_ERROR, "no errors");
});