rem: getDummyMsgHeader: function() { if (!this.mDummyHeader) this.mDummyHeader = { messageSize: 0, folder: null }; return this.mDummyHeader; 
add: getDummyMsgHeader: function() { if (!this.mDummyMsgHeader) this.mDummyMsgHeader = new nsDummyMsgHeader(); return this.mDummyMsgHeader; 
context:     getDummyMsgHeader: function() {      if (!this.mDummyHeader)        this.mDummyHeader = { messageSize: 0, folder: null };      return this.mDummyHeader;    }
meta: 9421	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/9421/fe07aedeea0c9be3af990dba4844697f2a13c40e/msgHdrViewOverlay.js/clean/mailnews/base/resources/content/msgHdrViewOverlay.js