[ES6 modules] ModuleTreeLinker::Instantiate shouldn't proceed on invalid context

third_party/WebKit/Source/core/testing/DummyModulator.cpp

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/testing/DummyModulator.h"
 
 #include "bindings/core/v8/ScriptValue.h"
 #include "core/dom/ScriptModuleResolver.h"
 
 namespace blink {
@@ skipping 73 matching lines @@
   NOTREACHED();
   return nullptr;
 }
 
 void DummyModulator::FetchNewSingleModule(const ModuleScriptFetchRequest&,
                                           ModuleGraphLevel,
                                           ModuleScriptLoaderClient*) {
   NOTREACHED();
 }
 
+bool DummyModulator::HasValidContext() {
+  return true;
+}
+
 ScriptModule DummyModulator::CompileModule(const String& script,
                                            const String& url_str,
                                            AccessControlStatus) {
   NOTREACHED();
   return ScriptModule();
 }
 
 ScriptValue DummyModulator::InstantiateModule(ScriptModule) {
   NOTREACHED();
   return ScriptValue();
 }
 
 ScriptValue DummyModulator::GetInstantiationError(const ModuleScript*) {
   NOTREACHED();
   return ScriptValue();
 }
 
 Vector<String> DummyModulator::ModuleRequestsFromScriptModule(ScriptModule) {
   NOTREACHED();
   return Vector<String>();
 }
 
 void DummyModulator::ExecuteModule(const ModuleScript*) {
   NOTREACHED();
 }
 
 }  // namespace blink