Detect <link rel='manifest'> and notify embedder.

Source/web/FrameLoaderClientImpl.cpp

 /*
  * Copyright (C) 2009, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2011 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
@@ skipping 791 matching lines @@
         return nullptr;
     return adoptPtr(m_webFrame->client()->createApplicationCacheHost(m_webFrame, client));
 }
 
 void FrameLoaderClientImpl::didStopAllLoaders()
 {
     if (m_webFrame->client())
         m_webFrame->client()->didAbortLoading(m_webFrame);
 }
 
+void FrameLoaderClientImpl::dispatchDidChangeManifest()
+{
+    if (m_webFrame->client())
+        m_webFrame->client()->didChangeManifest(m_webFrame);
+}
+
 } // namespace blink