Bug 374334 - Uncaught exception with cloneNode method and frameset element. Patch by Alex Vincent <ajvincent@gmail.com>. r=jst,sr=jst

content/events/src/nsEventListenerManager.cpp

@@ -826,6 +826,10 @@ nsEventListenerManager::AddScriptEventListener(nsISupports *aObject,
                                           aBody,
                                           url.get(), lineNo,
                                           handler);
+        if (rv == NS_ERROR_ILLEGAL_VALUE) {
+          NS_WARNING("Probably a syntax error in the event handler!");
+          return NS_SUCCESS_LOSS_OF_INSIGNIFICANT_DATA;
+        }
         NS_ENSURE_SUCCESS(rv, rv);
         // And bind it.
         rv = context->BindCompiledEventHandler(aObject, scope,

dom/src/base/nsJSEnvironment.cpp

@@ -1671,7 +1671,7 @@ nsJSContext::CompileEventHandler(nsIAtom *aName,
                                           aURL, aLineNo);
 
   if (!fun) {
-    return NS_ERROR_FAILURE;
+    return NS_ERROR_ILLEGAL_VALUE;
   }
 
   JSObject *handler = ::JS_GetFunctionObject(fun);