NoState Prefetch: nostate prefetch browser tests.

chrome/browser/prerender/prerender_contents.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_
 #define CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 186 matching lines @@
 
   // The prerender WebContents (may be NULL).
   content::WebContents* prerender_contents() const {
     return prerender_contents_.get();
   }
 
   std::unique_ptr<content::WebContents> ReleasePrerenderContents();
 
   // Sets the final status, calls OnDestroy and adds |this| to the
   // PrerenderManager's pending deletes list.
-  void Destroy(FinalStatus reason);
+  virtual void Destroy(FinalStatus reason);

[droger, 2016/09/20 10:57:19]

Add a comment:
// Virtual for testing.

I think it would be fine to have the observer in the base class instead, but I
don't have a strong preference.

[mattcary, 2016/09/21 08:45:10]

That's not a bad idea. Why multiply observers if we don't need to?

And looking closer, it seems that OnPrerenderStop already fits the bill, so I
don't need a new OnDestroy call. Yay!

I did take this opportunity to clean up the observer class which was a little
messy.

 
   // Called by the history tab helper with the information that it woudl have
   // added to the history service had this web contents not been used for
   // prerendering.
   void DidNavigate(const history::HistoryAddPageArgs& add_page_args);
 
   // Applies all the URL history encountered during prerendering to the
   // new tab.
   void CommitHistory(content::WebContents* tab);
 
@@ skipping 146 matching lines @@
   // A running tally of the number of bytes this prerender has caused to be
   // transferred over the network for resources.  Updated with AddNetworkBytes.
   int64_t network_bytes_;
 
   DISALLOW_COPY_AND_ASSIGN(PrerenderContents);
 };
 
 }  // namespace prerender
 
 #endif  // CHROME_BROWSER_PRERENDER_PRERENDER_CONTENTS_H_