lib/Ext/util/Collection.js
function(item) {
        var key = this.getKey(item);
        if (key) {
            return this.containsKey(key);
        } else {
            return Ext.Array.contains(this.items, item);
        }
    }
function(item) {
        var key = this.getKey(item);
        if (key) {
            return this.containsKey(key);
        } else {
            return Ext.Array.contains(this.items, item);
        }
    }
Returns `true` if the collection contains the passed Object as an item.
@param {Object} item The Object to look for in the collection.
@return {Boolean} `true` if the collection contains the Object as an item.