Merge r2636 to trunk

src/objects-inl.h

Index: src/objects-inl.h
===================================================================
--- src/objects-inl.h	(revision 2644)
+++ src/objects-inl.h	(working copy)
@@ -100,6 +100,25 @@
   }
 
 
+bool Object::IsInstanceOf(FunctionTemplateInfo* expected) {
+  // There is a constraint on the object; check.
+  if (!this->IsJSObject()) return false;
+  // Fetch the constructor function of the object.
+  Object* cons_obj = JSObject::cast(this)->map()->constructor();
+  if (!cons_obj->IsJSFunction()) return false;
+  JSFunction* fun = JSFunction::cast(cons_obj);
+  // Iterate through the chain of inheriting function templates to
+  // see if the required one occurs.
+  for (Object* type = fun->shared()->function_data();
+       type->IsFunctionTemplateInfo();
+       type = FunctionTemplateInfo::cast(type)->parent_template()) {
+    if (type == expected) return true;
+  }
+  // Didn't find the required type in the inheritance chain.
+  return false;
+}
+
+
 bool Object::IsSmi() {
   return HAS_SMI_TAG(this);
 }