Recalculation of height on resize event may cause null error

[cowardcalf]

It could happen when the component unmounting, a resize event triggered but the event listener of resize hasn't been removed.

In my case, it's like the code below:

<ReactMedia query="(max-width: 768px)" render={() => (
  <Headroom>{/* some components */}<Headroom>
)} />

When resizing the window by dragging, from width small than 768px to a larger one, it may throw the error:

_this.setHeightOffset = function () {
_this.setState({
height: _this.inner.offsetHeight
});
_this.resizeTicking = false;
};

It's easy to reproduce in developer tools of Chrome.
Also, it happens in Edge, IE as well.

I have to set calcHeightOnResize={false} to avoid this error.
BTW, although since v2.2.0 the option of calcHeightOnResize has been added, there is no document mention that.