 width;
    canvas.height = height;
    var ctx = canvas.getContext('bitmaprenderer');
    createImageBitmap(canvas).then(t.step_func_done(function(image) {
        assert_equals(image.width, width);
        assert_equals(image.height, height);

        var dstCanvas = document.createElement('canvas');
        dstCanvas.width = width;
        dstCanvas.height = height;
        var dstCtx = dstCanvas.getContext('2d');
        dstCtx.drawImage(canvas, 0, 0);
        testCanvas(dstCtx, 5, 5, 0, 0, 0, 0);
    }