Revert of "Speculatively launch Service Workers on mouse/touch events."

third_party/WebKit/public/platform/WebPrescientNetworking.h

 /*
  * Copyright (C) 2013 Google 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.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 19 matching lines @@
 
 #ifndef WebPrescientNetworking_h
 #define WebPrescientNetworking_h
 
 #include "WebCommon.h"
 #include "WebString.h"
 #include "WebURL.h"
 
 namespace blink {
 
-enum class WebNavigationHintType;
-
 class WebPrescientNetworking {
  public:
   virtual ~WebPrescientNetworking() {}
 
   // When a page navigation is speculated, DNS prefetch is triggered to hide
   // the host resolution latency.
   virtual void prefetchDNS(const WebString& hostname) {}
 
   virtual void preconnect(const WebURL& url, const bool allowCredentials) {}
-
-  // Send a hint that a navigation to |url| is likely to happen.
-  virtual void sendNavigationHint(const WebURL& url, WebNavigationHintType) {}
 };
 
 }  // namespace blink
 
 #endif  // WebPrescientNetworking_h