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: 5459	/local1/tlutelli/issta_data/temp/all_js/javascript/2006_temp/2006/5459/90d39b5ad3d6cd80a60d14b918774aba39d2fda1/msgHdrViewOverlay.js/buggy/mailnews/base/resources/content/msgHdrViewOverlay.js