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, 12 insertions, 8 deletions

diff --git a/fxjs/xfa/cjx_signaturepseudomodel.cpp b/fxjs/xfa/cjx_signaturepseudomodel.cpp
index 20cb5dcccf..49a4f1540f 100644
--- a/fxjs/xfa/cjx_signaturepseudomodel.cpp
+++ b/fxjs/xfa/cjx_signaturepseudomodel.cpp
@@ -30,30 +30,34 @@ CJS_Return CJX_SignaturePseudoModel::verifySignature(
     CFX_V8* runtime,
     const std::vector<v8::Local<v8::Value>>& params) {
   if (params.empty() || params.size() > 4)
-    return CJS_Return(JSGetStringFromID(JSMessage::kParamError));
-  return CJS_Return(runtime->NewNumber(0));
+    return CJS_Return::Failure(JSMessage::kParamError);
+
+  return CJS_Return::Success(runtime->NewNumber(0));
 }
 
 CJS_Return CJX_SignaturePseudoModel::sign(
     CFX_V8* runtime,
     const std::vector<v8::Local<v8::Value>>& params) {
   if (params.size() < 3 || params.size() > 7)
-    return CJS_Return(JSGetStringFromID(JSMessage::kParamError));
-  return CJS_Return(runtime->NewBoolean(false));
+    return CJS_Return::Failure(JSMessage::kParamError);
+
+  return CJS_Return::Success(runtime->NewBoolean(false));
 }
 
 CJS_Return CJX_SignaturePseudoModel::enumerate(
     CFX_V8* runtime,
     const std::vector<v8::Local<v8::Value>>& params) {
   if (!params.empty())
-    return CJS_Return(JSGetStringFromID(JSMessage::kParamError));
-  return CJS_Return();
+    return CJS_Return::Failure(JSMessage::kParamError);
+
+  return CJS_Return::Success();
 }
 
 CJS_Return CJX_SignaturePseudoModel::clear(
     CFX_V8* runtime,
     const std::vector<v8::Local<v8::Value>>& params) {
   if (params.empty() || params.size() > 2)
-    return CJS_Return(JSGetStringFromID(JSMessage::kParamError));
-  return CJS_Return(runtime->NewBoolean(false));
+    return CJS_Return::Failure(JSMessage::kParamError);
+
+  return CJS_Return::Success(runtime->NewBoolean(false));
 }