Introduce safer CJS_Return::Success() and Failure().

Avoid the possibility of ever re-introducing the issue noticed
last week.

Remove some redundant JSGetStringFromID() calls.

Change-Id: I56687c2191bd72e378f747083f34080e50cbe490
Reviewed-on: https://pdfium-review.googlesource.com/40490
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Tom Sepez <tsepez@chromium.org>

1 files changed, 9 insertions, 8 deletions

diff --git a/fxjs/xfa/cjx_model.cpp b/fxjs/xfa/cjx_model.cpp
index d94a1b68fd..97d25175fe 100644
--- a/fxjs/xfa/cjx_model.cpp
+++ b/fxjs/xfa/cjx_model.cpp
@@ -28,14 +28,14 @@ CJX_Model::~CJX_Model() {}
 CJS_Return CJX_Model::clearErrorList(
     CFX_V8* runtime,
     const std::vector<v8::Local<v8::Value>>& params) {
-  return CJS_Return();
+  return CJS_Return::Success();
 }
 
 CJS_Return CJX_Model::createNode(
     CFX_V8* runtime,
     const std::vector<v8::Local<v8::Value>>& params) {
   if (params.empty() || params.size() > 3)
-    return CJS_Return(JSGetStringFromID(JSMessage::kParamError));
+    return CJS_Return::Failure(JSMessage::kParamError);
 
   WideString name;
   if (params.size() > 1)
@@ -49,11 +49,11 @@ CJS_Return CJX_Model::createNode(
   XFA_Element eType = CXFA_Node::NameToElement(tagName);
   CXFA_Node* pNewNode = GetXFANode()->CreateSamePacketNode(eType);
   if (!pNewNode)
-    return CJS_Return(runtime->NewNull());
+    return CJS_Return::Success(runtime->NewNull());
 
   if (!name.IsEmpty()) {
     if (!pNewNode->HasAttribute(XFA_Attribute::Name))
-      return CJS_Return(JSGetStringFromID(JSMessage::kParamError));
+      return CJS_Return::Failure(JSMessage::kParamError);
 
     pNewNode->JSObject()->SetAttribute(XFA_Attribute::Name, name.AsStringView(),
                                        true);
@@ -64,22 +64,23 @@ CJS_Return CJX_Model::createNode(
   CFXJSE_Value* value =
       GetDocument()->GetScriptContext()->GetJSValueFromMap(pNewNode);
   if (!value)
-    return CJS_Return(runtime->NewNull());
+    return CJS_Return::Success(runtime->NewNull());
 
-  return CJS_Return(value->DirectGetValue().Get(runtime->GetIsolate()));
+  return CJS_Return::Success(
+      value->DirectGetValue().Get(runtime->GetIsolate()));
 }
 
 CJS_Return CJX_Model::isCompatibleNS(
     CFX_V8* runtime,
     const std::vector<v8::Local<v8::Value>>& params) {
   if (params.empty())
-    return CJS_Return(JSGetStringFromID(JSMessage::kParamError));
+    return CJS_Return::Failure(JSMessage::kParamError);
 
   WideString nameSpace;
   if (params.size() >= 1)
     nameSpace = runtime->ToWideString(params[0]);
 
-  return CJS_Return(
+  return CJS_Return::Success(
       runtime->NewBoolean(TryNamespace().value_or(WideString()) == nameSpace));
 }