lib/Ext/util/Collection.js
function(item) {
        var index = this.items.indexOf(item);
        if (index === -1) {
            Ext.Array.remove(this.all, item);

            if (typeof this.getKey == 'function') {
                var key = this.getKey(item);
                if (key !== undefined) {
                    delete this.map[key];
                }
            }

            return item;
        }
        return this.removeAt(this.items.indexOf(item));
    }
function(item) {
        var index = this.items.indexOf(item);
        if (index === -1) {
            Ext.Array.remove(this.all, item);

            if (typeof this.getKey == 'function') {
                var key = this.getKey(item);
                if (key !== undefined) {
                    delete this.map[key];
                }
            }

            return item;
        }
        return this.removeAt(this.items.indexOf(item));
    }
Remove an item from the collection.
@param {Object} item The item to remove.
@return {Object} The item removed or `false` if no item was removed.