query trimming now works properly on searchquerycommitted

Summary: query trimming was broken due to searchquerycommited passing an object instead of a string

Test Plan: tested manually. Unit tests

Reviewers: bengotow

Reviewed By: bengotow

Differential Revision: https://phab.nylas.com/D1763

src/flux/stores/focused-category-store.coffee

@@ -32,6 +32,8 @@ class FocusedCategoryStore extends NylasStore
     @_setCategory(category)
 
   _onSearchQueryCommitted: (query="") ->
+    if typeof(query) != "string"
+      query = query[0].all
     if query.trim().length > 0 and @_category
       @_categoryBeforeSearch = @_category
       @_setCategory(null)