Add a signal to the scheduler that a navigation is expected

third_party/WebKit/Source/core/loader/NavigationScheduler.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2009 Adam Barth. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  *
@@ skipping 402 matching lines @@
 {
     if (!m_redirect)
         return;
 
     ASSERT(m_frame->page());
     if (m_navigateTaskFactory->isPending())
         return;
     if (!m_redirect->shouldStartTimer(m_frame))
         return;
 
-    Platform::current()->currentThread()->scheduler()->loadingTaskRunner()->postDelayedTask(
+    WebScheduler* scheduler = Platform::current()->currentThread()->scheduler();
+    scheduler->onNavigationExpected();
+    scheduler->loadingTaskRunner()->postDelayedTask(
         FROM_HERE, m_navigateTaskFactory->cancelAndCreate(), m_redirect->delay() * 1000.0);
 
     InspectorInstrumentation::frameScheduledNavigation(m_frame, m_redirect->delay());
 }
 
 void NavigationScheduler::cancel()
 {
-    if (m_navigateTaskFactory->isPending())
+    if (m_navigateTaskFactory->isPending()) {
+        Platform::current()->currentThread()->scheduler()->onNavigationCanceled();
         InspectorInstrumentation::frameClearedScheduledNavigation(m_frame);
+    }
     m_navigateTaskFactory->cancel();
     m_redirect.clear();
 }
 
 DEFINE_TRACE(NavigationScheduler)
 {
     visitor->trace(m_frame);
     visitor->trace(m_redirect);
 }
 
 } // namespace blink