Fix the ChromeFrame net tests dchecks in debug builds due to a missing AtExitManager instance.

chrome_frame/test/net/fake_external_tab.cc

Index: chrome_frame/test/net/fake_external_tab.cc
===================================================================
--- chrome_frame/test/net/fake_external_tab.cc	(revision 101850)
+++ chrome_frame/test/net/fake_external_tab.cc	(working copy)
@@ -231,6 +231,9 @@
 
 void FakeExternalTab::Initialize() {
   DCHECK(g_browser_process == NULL);
+
+  notificaton_service_.reset(new NotificationService);
+
   base::SystemMonitor system_monitor;
 
   icu_util::Initialize();
@@ -560,8 +563,6 @@
   google_breakpad::scoped_ptr<google_breakpad::ExceptionHandler> breakpad(
       InitializeCrashReporting(HEADLESS));
 
-  NotificationService service;
-
   // TODO(tommi): Stuff be broke. Needs a fixin'.
   // This is awkward: the TestSuite derived CFUrlRequestUnittestRunner contains
   // the instance of the AtExitManager that RegisterPathProvider() and others