Support for global var shortcuts in script contexts.

src/runtime/runtime-scopes.cc

Index: src/runtime/runtime-scopes.cc
diff --git a/src/runtime/runtime-scopes.cc b/src/runtime/runtime-scopes.cc
index 8b34b6ced704b19774be896fa82092af9cf701dd..700925db622d718cd1497707de9058aa6c691337 100644
--- a/src/runtime/runtime-scopes.cc
+++ b/src/runtime/runtime-scopes.cc
@@ -632,7 +632,6 @@ RUNTIME_FUNCTION(Runtime_NewScriptContext) {
   Handle<ScriptContextTable> script_context_table(
       native_context->script_context_table());
 
-  Handle<String> clashed_name;
   Object* name_clash_result =
       FindNameClash(scope_info, global_object, script_context_table);
   if (isolate->has_pending_exception()) return name_clash_result;
@@ -640,12 +639,16 @@ RUNTIME_FUNCTION(Runtime_NewScriptContext) {
   // Script contexts have a canonical empty function as their closure, not the
   // anonymous closure containing the global code.  See
   // FullCodeGenerator::PushFunctionArgumentForContextAllocation.
-  Handle<JSFunction> closure(native_context->closure());
+  Handle<JSFunction> closure(global_object->IsJSBuiltinsObject()
+                                 ? *function
+                                 : native_context->closure());
   Handle<Context> result =
       isolate->factory()->NewScriptContext(closure, scope_info);
 
+  result->InitializeGlobalSlots();
+
   DCHECK(function->context() == isolate->context());
-  DCHECK(function->context()->global_object() == result->global_object());
+  DCHECK(*global_object == result->global_object());
 
   Handle<ScriptContextTable> new_script_context_table =
       ScriptContextTable::Extend(script_context_table, result);