Stack traces exposed to Javascript should omit extensions.

src/objects-inl.h

Index: src/objects-inl.h
diff --git a/src/objects-inl.h b/src/objects-inl.h
index 50c9f3c28d49f40ff5236cfe93c2dd4db21fe800..95b257229972cf9bbb177f649bc6b56654549f81 100644
--- a/src/objects-inl.h
+++ b/src/objects-inl.h
@@ -5657,7 +5657,7 @@ bool JSFunction::IsBuiltin() {
 }
 
 
-bool JSFunction::IsNative() {
+bool JSFunction::IsFromNativeScript() {
   Object* script = shared()->script();
   bool native = script->IsScript() &&
                 Script::cast(script)->type()->value() == Script::TYPE_NATIVE;
@@ -5666,6 +5666,13 @@ bool JSFunction::IsNative() {
 }
 
 
+bool JSFunction::IsFromExtensionScript() {
+  Object* script = shared()->script();
+  return script->IsScript() &&
+         Script::cast(script)->type()->value() == Script::TYPE_EXTENSION;
+}
+
+
 bool JSFunction::NeedsArgumentsAdaption() {
   return shared()->formal_parameter_count() !=
       SharedFunctionInfo::kDontAdaptArgumentsSentinel;