Make the I in IFormFiller explicit

xfa/fxfa/parser/cxfa_document.cpp

Index: xfa/fxfa/parser/cxfa_document.cpp
diff --git a/xfa/fxfa/parser/cxfa_document.cpp b/xfa/fxfa/parser/cxfa_document.cpp
index 346690b484d84b0dedf23b30d7260977805ca470..a80d842325ee6f7f033e83b5d48ede244ef84a98 100644
--- a/xfa/fxfa/parser/cxfa_document.cpp
+++ b/xfa/fxfa/parser/cxfa_document.cpp
@@ -269,10 +269,10 @@ FX_BOOL CXFA_Document::IsInteractive() {
   if (!pPDF)
     return FALSE;
 
-  CXFA_Node* pInteractive = pPDF->GetChild(0, XFA_Element::Interactive);
-  if (pInteractive) {
+  CXFA_Node* pFormFiller = pPDF->GetChild(0, XFA_Element::Interactive);
+  if (pFormFiller) {
     m_dwDocFlags |= XFA_DOCFLAG_HasInteractive;
-    if (pInteractive->TryContent(wsInteractive) &&
+    if (pFormFiller->TryContent(wsInteractive) &&
         wsInteractive == FX_WSTRC(L"1")) {
       m_dwDocFlags |= XFA_DOCFLAG_Interactive;
       return TRUE;