Make functions being routed by NativeHandlers throw an exception if there is no ModuleSystem in the…

chrome/renderer/module_system.cc

 // Copyright (c) 2012 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 "chrome/renderer/module_system.h"
 
 #include "base/bind.h"
 #include "third_party/WebKit/Source/WebKit/chromium/public/WebScopedMicrotaskSuppression.h"
 
 namespace {
@@ skipping 41 matching lines @@
     ModuleSystem* module_system)
     : module_system_(module_system) {
   module_system_->natives_enabled_++;
 }
 
 ModuleSystem::NativesEnabledScope::~NativesEnabledScope() {
   module_system_->natives_enabled_--;
   CHECK_GE(module_system_->natives_enabled_, 0);
 }
 
+// static
+bool ModuleSystem::IsPresentInCurrentContext() {
+  v8::Handle<v8::Object> global(v8::Context::GetCurrent()->Global());
+  return !global->GetHiddenValue(v8::String::New(kModuleSystem))->IsUndefined();
+}
+
 void ModuleSystem::Require(const std::string& module_name) {
   v8::HandleScope handle_scope;
   RequireForJsInner(v8::String::New(module_name.c_str()));
 }
 
 v8::Handle<v8::Value> ModuleSystem::RequireForJs(const v8::Arguments& args) {
   v8::HandleScope handle_scope;
   v8::Handle<v8::String> module_name = args[0]->ToString();
   return handle_scope.Close(RequireForJsInner(module_name));
 }
@@ skipping 138 matching lines @@
   v8::Handle<v8::String> left =
       v8::String::New("(function(require, requireNative, exports) {");
   v8::Handle<v8::String> right = v8::String::New("\n})");
   return handle_scope.Close(
       v8::String::Concat(left, v8::String::Concat(source, right)));
 }
 
 v8::Handle<v8::Value> ModuleSystem::ThrowException(const std::string& message) {
   return v8::ThrowException(v8::String::New(message.c_str()));
 }