code: function(o) {
          var me = this,
              removeKey,
              index;
  
          // If
          //     We have not been forced into using linear lookup by a usage of the 2 arg form of add
          // and
          //     The key extraction function yields a key
          // Then use indexOfKey. This will use the indexMap - rebuilding it if necessary.
          if (!me.useLinearSearch && (removeKey = me.getKey(o))) {
              index = me.indexOfKey(removeKey);
          }
  
          // Otherwise we have to do it the slow way with a linear search.
          else {
              index = Ext.Array.indexOf(me.items, o);
          }
  
          return (index === -1) ? false : me.removeAt(index);
      }
docs: Remove an item from the collection.
  @param {Object} o The item to remove.
  @return {Object} The item removed or false if no item was removed.
  @since Ext 1