add: if (!this.mSelectDocs) return;  
context:   removeClickListeners: function()  {    for (var i = 0; i < this.mSelectDocs.length; ++i) {      this.mSelectDocs[i].removeEventListener("mousedown", MouseDownListener, true);      this.mSelectDocs[i].removeEventListener("mouseup", EventCanceller, true);      this.mSelectDocs[i].removeEventListener("click", ListenerRemover, true);      this.mSelectDocs[i].removeEventListener("mouseout", ListenerRemover, true);    }  },
meta: 10234	/local1/tlutelli/issta_data/temp/all_js/javascript/2007_temp/2007/10234/08dd0915136da801bf3dbbd6cfd275672a11b8fc/dom.js/clean/extensions/inspector/resources/content/viewers/dom/dom.js