Add missing runtime assert for LiveEdit.

R=ulan@chromium.org

Review URL: https://codereview.chromium.org/227043009

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@20542 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/runtime.cc

@@ -13556,6 +13556,7 @@ RUNTIME_FUNCTION(MaybeObject*, Runtime_LiveEditPatchFunctionPositions) {
   ASSERT(args.length() == 2);
   CONVERT_ARG_HANDLE_CHECKED(JSArray, shared_array, 0);
   CONVERT_ARG_HANDLE_CHECKED(JSArray, position_change_array, 1);
+  RUNTIME_ASSERT(SharedInfoWrapper::IsInstance(shared_array))
 
   LiveEdit::PatchFunctionPositions(shared_array, position_change_array);
   return isolate->heap()->undefined_value();