Add WebPrescientNetworking to trigger preconnect from Blink.

Source/Platform/chromium/public/WebPrerenderingSupport.h

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  * modification, are permitted provided that the following conditions are
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@@ skipping 14 matching lines @@
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 #ifndef WebPrerenderingSupport_h
 #define WebPrerenderingSupport_h
 
 #include "WebCommon.h"
+#include "WebPreconnectMotivation.h"
 
 namespace WebKit {
 
 class WebPrerender;
+class WebURL;
 
 class WebPrerenderingSupport {
 public:
     WEBKIT_EXPORT static void initialize(WebPrerenderingSupport*);
     WEBKIT_EXPORT static void shutdown();
     WEBKIT_EXPORT static WebPrerenderingSupport* current();
 
+    // When a page navigation is speculated, preconnect is triggered to hide
+    // session initialization latency to the server providing the page resource.

[kouhei (in TOK), 2013/05/09 01:08:34]

Changed comment. Does it make sense now?

[tkent, 2013/05/09 02:33:55]

Yeah, it makes sense.

+    virtual void preconnect(const WebURL& url,
+                            WebPreconnectMotivation motivation) = 0;
+
     // A prerender link element is added when it is inserted into a document.
     virtual void add(const WebPrerender&) = 0;
 
     // A prerender is canceled when it is removed from a document.
     virtual void cancel(const WebPrerender&) = 0;
 
     // A prerender is abandoned when it's navigated away from or suspended in the page cache. This
     // is a weaker signal than cancel(), since the launcher hasn't indicated that the prerender isn't
     // wanted, and we may end up using it after, for instance, a short redirect chain.
     virtual void abandon(const WebPrerender&) = 0;
 
 protected:
     WebPrerenderingSupport() { }
     virtual ~WebPrerenderingSupport() { }
 
 private:
     static WebPrerenderingSupport* s_platform;
 };
 
 } // namespace WebKit
 
 #endif // WebPrerenderingSupport_h