Make exception throwing more robust in V8 out-of-stack situations

Source/bindings/core/v8/V8ThrowException.cpp

Index: Source/bindings/core/v8/V8ThrowException.cpp
diff --git a/Source/bindings/core/v8/V8ThrowException.cpp b/Source/bindings/core/v8/V8ThrowException.cpp
index 13be07f40bc91f1c7f5d9f48e710c7875800dd9b..67421e13eacb11cfb7b93ea2fd0bb430ca76b803 100644
--- a/Source/bindings/core/v8/V8ThrowException.cpp
+++ b/Source/bindings/core/v8/V8ThrowException.cpp
@@ -70,12 +70,16 @@ v8::Handle<v8::Value> V8ThrowException::createDOMException(v8::Isolate* isolate,
     if (!frame || !BindingSecurity::shouldAllowAccessToFrame(isolate, frame, DoNotReportSecurityError))
         sanitizedCreationContext = isolate->GetCurrentContext()->Global();
 
+    v8::TryCatch tryCatch;
 
     RefPtrWillBeRawPtr<DOMException> domException = DOMException::create(ec, sanitizedMessage, unsanitizedMessage);
     v8::Handle<v8::Value> exception = toV8(domException.get(), sanitizedCreationContext, isolate);
 
-    if (exception.IsEmpty())
+    if (!exception.IsEmpty()) {
+        if (tryCatch.HasCaught())
+            return tryCatch.Exception();
         return v8Undefined();
+    }

[haraken, 2015/02/04 09:41:41]

I might be misunderstanding but why is this not like:

if (tryCatch.HasCaught()) {
  ASSERT(exception.IsEmpty());
  return tryCatch.Exception();
}
ASSERT(!exception.IsEmpty());

?

[Jens Widell, 2015/02/04 09:48:01]

Oups, this was meant to be "if (exception.IsEmpty())" still. The added negation
is a left-over from a slightly different change that I made and then decided
against, and failed to undo completely.

I have no reason to doubt those are accurate assertions. I'll change to that.

[Jens Widell, 2015/02/04 09:50:52]

Done.

 
     // Attach an Error object to the DOMException. This is then lazily used to get the stack value.
     v8::Handle<v8::Value> error = v8::Exception::Error(v8String(isolate, domException->message()));