_handleResizeDebounced can be called on unmounted component causing warning

[oliseviche]

During the resize phase the actual handleResize callback being delayed through debounce.

This could lead to the behaviour, when for example, component would being unmounted on certain display resolutions (mobiles for example), but the resize heandler would still be called - producing the warning about updating the dismounted component.

I guess, the debounce also should be stopped in componentWillUnmount callback, the same as this._cancelTimeoutAnimations and this._removeEventListeners