Helper function that scrolls the view towards a view-sequence node.
function _ensureVisibleSequence(viewSequence, next) {
        this._scroll.scrollToSequence = undefined;
        this._scroll.scrollToRenderNode = undefined;
        this._scroll.ensureVisibleRenderNode = viewSequence.get();
        this._scroll.scrollToDirection = next;
        this._scroll.scrollDirty = true;
    }