SearchBox query throttling doesn't work

[GregoryPotdevin]

When SearchBox's onChange method is called, the following code is used to generate a new search :

            throttle(()=> {
                this.searchQuery(this.accessor.getQueryString())
            }, 400)()

A new throttled searchQuery function is generated each time, so they just stack up without waiting for the 400ms delay. The throttle function should be created in the constructor or in componentWillMount and reused for every call.