Stack traces exposed to Javascript should omit extensions.

src/objects.h

Index: src/objects.h
diff --git a/src/objects.h b/src/objects.h
index 74aaedf58ba55a599e11704f9eecd339cb2ec76a..3e83eda46f82b11c190041a7e29b0dd6d12272e9 100644
--- a/src/objects.h
+++ b/src/objects.h
@@ -7634,7 +7634,10 @@ class JSFunction: public JSObject {
   inline bool IsBuiltin();
 
   // Tells whether this function is defined in a native script.
-  inline bool IsNative();
+  inline bool IsFromNativeScript();
+
+  // Tells whether this function is defined in an extension script.
+  inline bool IsFromExtensionScript();
 
   // Tells whether or not the function needs arguments adaption.
   inline bool NeedsArgumentsAdaption();