Add WebPrescientNetworking to trigger preconnect from Blink.

Source/Platform/chromium/public/WebPrerenderingSupport.h

Index: Source/Platform/chromium/public/WebPrerenderingSupport.h
diff --git a/Source/Platform/chromium/public/WebPrerenderingSupport.h b/Source/Platform/chromium/public/WebPrerenderingSupport.h
index a2672911fa50a83358d2bf4b0996fd5493806ba2..253e984e7794d34b3f0927289627274e294cbd68 100644
--- a/Source/Platform/chromium/public/WebPrerenderingSupport.h
+++ b/Source/Platform/chromium/public/WebPrerenderingSupport.h
@@ -32,10 +32,12 @@
 #define WebPrerenderingSupport_h
 
 #include "WebCommon.h"
+#include "WebPreconnectMotivation.h"
 
 namespace WebKit {
 
 class WebPrerender;
+class WebURL;
 
 class WebPrerenderingSupport {
 public:
@@ -43,6 +45,11 @@ public:
     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;