3 files changed, 28 insertions, 23 deletions

diff --git a/xfa/fxfa/parser/cxfa_dataexporter.cpp b/xfa/fxfa/parser/cxfa_dataexporter.cpp
index f7715dc374..c86a7f7d51 100644
--- a/xfa/fxfa/parser/cxfa_dataexporter.cpp
+++ b/xfa/fxfa/parser/cxfa_dataexporter.cpp
@@ -152,12 +152,13 @@ void RecognizeXFAVersionNumber(CXFA_Node* pTemplateRoot,
   if (!pTemplateRoot)
     return;
 
-  WideString wsTemplateNS;
-  if (!pTemplateRoot->JSNode()->TryNamespace(wsTemplateNS))
+  pdfium::Optional<WideString> templateNS =
+      pTemplateRoot->JSNode()->TryNamespace();
+  if (!templateNS)
     return;
 
   XFA_VERSION eVersion =
-      pTemplateRoot->GetDocument()->RecognizeXFAVersionNumber(wsTemplateNS);
+      pTemplateRoot->GetDocument()->RecognizeXFAVersionNumber(*templateNS);
   if (eVersion == XFA_VERSION_UNKNOWN)
     eVersion = XFA_VERSION_DEFAULT;
 
diff --git a/xfa/fxfa/parser/cxfa_document.cpp b/xfa/fxfa/parser/cxfa_document.cpp
index 82a71dea28..44fc9089c1 100644
--- a/xfa/fxfa/parser/cxfa_document.cpp
+++ b/xfa/fxfa/parser/cxfa_document.cpp
@@ -151,14 +151,16 @@ CXFA_Object* CXFA_Document::GetXFAObject(XFA_HashCode dwNodeNameHash) {
         if (pDatasetsChild->GetNameHash() != XFA_HASHCODE_Data)
           continue;
 
-        WideString wsNamespaceURI;
-        if (!pDatasetsChild->JSNode()->TryNamespace(wsNamespaceURI))
+        pdfium::Optional<WideString> namespaceURI =
+            pDatasetsChild->JSNode()->TryNamespace();
+        if (!namespaceURI)
           continue;
 
-        WideString wsDatasetsURI;
-        if (!pDatasetsNode->JSNode()->TryNamespace(wsDatasetsURI))
+        pdfium::Optional<WideString> datasetsURI =
+            pDatasetsNode->JSNode()->TryNamespace();
+        if (!datasetsURI)
           continue;
-        if (wsNamespaceURI == wsDatasetsURI)
+        if (*namespaceURI == *datasetsURI)
           return pDatasetsChild;
       }
       return nullptr;
diff --git a/xfa/fxfa/parser/xfa_document_datamerger_imp.cpp b/xfa/fxfa/parser/xfa_document_datamerger_imp.cpp
index 4cf7601531..89a6500fa6 100644
--- a/xfa/fxfa/parser/xfa_document_datamerger_imp.cpp
+++ b/xfa/fxfa/parser/xfa_document_datamerger_imp.cpp
@@ -1052,12 +1052,11 @@ CXFA_Node* MaybeCreateDataNode(CXFA_Document* pDocument,
       if (pDDGroupNode->GetElementType() != XFA_Element::DataGroup)
         continue;
 
-      WideString wsNamespace;
-      if (!pDDGroupNode->JSNode()->TryNamespace(wsNamespace) ||
-          wsNamespace != L"http://ns.adobe.com/data-description/") {
+      pdfium::Optional<WideString> ns = pDDGroupNode->JSNode()->TryNamespace();
+      if (!ns || *ns != L"http://ns.adobe.com/data-description/")
         continue;
-      }
     }
+
     CXFA_Node* pDDNode =
         pDDGroupNode->GetFirstChildByName(wsName.AsStringView());
     if (!pDDNode)
@@ -1231,12 +1230,12 @@ void UpdateDataRelation(CXFA_Node* pDataNode, CXFA_Node* pDataDescriptionNode) {
         if (pDDGroupNode->GetElementType() != XFA_Element::DataGroup)
           continue;
 
-        WideString wsNamespace;
-        if (!pDDGroupNode->JSNode()->TryNamespace(wsNamespace) ||
-            wsNamespace != L"http://ns.adobe.com/data-description/") {
+        pdfium::Optional<WideString> ns =
+            pDDGroupNode->JSNode()->TryNamespace();
+        if (!ns || *ns != L"http://ns.adobe.com/data-description/")
           continue;
-        }
       }
+
       CXFA_Node* pDDNode = pDDGroupNode->GetFirstChildByName(dwNameHash);
       if (!pDDNode)
         continue;
@@ -1398,8 +1397,8 @@ void CXFA_Document::DoDataMerge() {
     pDatasetsRoot->SetXMLMappingNode(pDatasetsXMLNode);
   }
   CXFA_Node *pDataRoot = nullptr, *pDDRoot = nullptr;
-  WideString wsDatasetsURI;
-  pDatasetsRoot->JSNode()->TryNamespace(wsDatasetsURI);
+  WideString wsDatasetsURI =
+      pDatasetsRoot->JSNode()->TryNamespace().value_or(WideString());
   for (CXFA_Node* pChildNode =
            pDatasetsRoot->GetNodeItem(XFA_NODEITEM_FirstChild);
        pChildNode;
@@ -1407,16 +1406,19 @@ void CXFA_Document::DoDataMerge() {
     if (pChildNode->GetElementType() != XFA_Element::DataGroup)
       continue;
 
-    WideString wsNamespaceURI;
     if (!pDDRoot && pChildNode->GetNameHash() == XFA_HASHCODE_DataDescription) {
-      if (!pChildNode->JSNode()->TryNamespace(wsNamespaceURI))
+      pdfium::Optional<WideString> namespaceURI =
+          pChildNode->JSNode()->TryNamespace();
+      if (!namespaceURI)
         continue;
-      if (wsNamespaceURI == L"http://ns.adobe.com/data-description/")
+      if (*namespaceURI == L"http://ns.adobe.com/data-description/")
         pDDRoot = pChildNode;
     } else if (!pDataRoot && pChildNode->GetNameHash() == XFA_HASHCODE_Data) {
-      if (!pChildNode->JSNode()->TryNamespace(wsNamespaceURI))
+      pdfium::Optional<WideString> namespaceURI =
+          pChildNode->JSNode()->TryNamespace();
+      if (!namespaceURI)
         continue;
-      if (wsNamespaceURI == wsDatasetsURI)
+      if (*namespaceURI == wsDatasetsURI)
         pDataRoot = pChildNode;
     }
     if (pDataRoot && pDDRoot)