Harden yet more runtime functions

src/liveedit.h

Index: src/liveedit.h
diff --git a/src/liveedit.h b/src/liveedit.h
index 5be63ac0a12618039fc1b2a68544a78481c064d8..f0b9dbfe45ae8717e89f3386747a2ce687384ea9 100644
--- a/src/liveedit.h
+++ b/src/liveedit.h
@@ -278,9 +278,12 @@ class FunctionInfoWrapper : public JSArrayBasedStruct<FunctionInfoWrapper> {
 class SharedInfoWrapper : public JSArrayBasedStruct<SharedInfoWrapper> {
  public:
   static bool IsInstance(Handle<JSArray> array) {
-    return array->length() == Smi::FromInt(kSize_) &&
-        Object::GetElement(array->GetIsolate(), array, kSharedInfoOffset_)
-            .ToHandleChecked()->IsJSValue();
+    if (array->length() != Smi::FromInt(kSize_)) return false;
+    Isolate* iso = array->GetIsolate();

[Dmitry Lomov (no reviews), 2014/05/07 14:47:18]

nit: iso -> isolate
('iso' is never used as an abbreviation for 'isolate' in the code)

[Jakob Kummerow, 2014/05/08 09:32:57]

Done.

+    Handle<Object> element(
+        Object::GetElement(iso, array, kSharedInfoOffset_).ToHandleChecked());
+    if (!element->IsJSValue()) return false;
+    return Handle<JSValue>::cast(element)->value()->IsSharedFunctionInfo();
   }
 
   explicit SharedInfoWrapper(Handle<JSArray> array)