mIsPopup(PR_FALSE)
mIsPopup(PR_FALSE), mHiddenForm(nsnull)
XULDocumentImpl::XULDocumentImpl(void)    : mDocumentURL(nsnull),      mDocumentURLGroup(nsnull),      mRootContent(nsnull),      mParentDocument(nsnull),      mScriptContextOwner(nsnull),      mScriptObject(nsnull),      mSelection(nsnull),      mDisplaySelection(PR_FALSE),      mNameSpaceManager(nsnull),      mAttrStyleSheet(nsnull),      mCSSLoader(nsnull),      mBuilders(nsnull),      mXULBuilder(nsnull),      mLocalDataSource(nsnull),      mDocumentDataSource(nsnull),      mCharSetID("UTF-8"),      mLineBreaker(nsnull),      mWordBreaker(nsnull),      mContentViewerContainer(nsnull),      mCommand(""),      mFragmentRoot(nsnull),      mListenerManager(nsnull),	    mPopup(nsnull),      mIsPopup(PR_FALSE){    NS_INIT_REFCNT();    nsresult rv;    // construct a selection object    if (NS_FAILED(rv = nsComponentManager::CreateInstance(kRangeListCID,                                                    nsnull,                                                    kIDOMSelectionIID,                                                    (void**) &mSelection))) {        NS_ERROR("unable to create DOM selection");    }    if (gRefCnt++ == 0) {        kIdAtom        = NS_NewAtom("id");        kObservesAtom  = NS_NewAtom("observes");        // Keep the RDF service cached in a member variable to make using        // it a bit less painful        rv = nsServiceManager::GetService(kRDFServiceCID,                                          kIRDFServiceIID,                                          (nsISupports**) &gRDFService);        NS_ASSERTION(NS_SUCCEEDED(rv), "unable to get RDF Service");        if (gRDFService) {            gRDFService->GetResource(kURIRDF_instanceOf, &kRDF_instanceOf);            gRDFService->GetResource(kURIRDF_type,       &kRDF_type);            gRDFService->GetResource(kURIXUL_element,    &kXUL_element);        }    }#ifdef PR_LOGGING    if (! gMapLog)        gMapLog = PR_NewLogModule("nsXULDocumentElementMap");#endif}