Add IsEmpty() check to ModuleSystem::IsPresentInCurrentContext().

chrome/renderer/extensions/module_system.cc

Index: chrome/renderer/extensions/module_system.cc
diff --git a/chrome/renderer/extensions/module_system.cc b/chrome/renderer/extensions/module_system.cc
index f87f48b7c6ffc70289759ed982ee848bb2187389..594f645377750507d543c3eab99b98661ecfc88f 100644
--- a/chrome/renderer/extensions/module_system.cc
+++ b/chrome/renderer/extensions/module_system.cc
@@ -56,6 +56,8 @@ ModuleSystem::NativesEnabledScope::~NativesEnabledScope() {
 // static
 bool ModuleSystem::IsPresentInCurrentContext() {
   v8::Handle<v8::Object> global(v8::Context::GetCurrent()->Global());
+  if (global.IsEmpty())
+    return false;
   v8::Handle<v8::Value> module_system =
       global->GetHiddenValue(v8::String::New(kModuleSystem));
   return !module_system.IsEmpty() && !module_system->IsUndefined();