Modifying prefetch to account for multi-profile.

chrome/browser/net/connect_interceptor.h

Index: chrome/browser/net/connect_interceptor.h
===================================================================
--- chrome/browser/net/connect_interceptor.h	(revision 96009)
+++ chrome/browser/net/connect_interceptor.h	(working copy)
@@ -6,30 +6,35 @@
 #define CHROME_BROWSER_NET_CONNECT_INTERCEPTOR_H_
 #pragma once
 
-#include "net/url_request/url_request.h"
+#include "net/url_request/url_request_job_factory.h"
 
 #include "base/gtest_prod_util.h"
 #include "base/memory/mru_cache.h"
+#include "base/time.h"
 
 namespace chrome_browser_net {
 
+class Predictor;
+
 //------------------------------------------------------------------------------
 // An interceptor to monitor URLRequests so that we can do speculative DNS
 // resolution and/or speculative TCP preconnections.
-class ConnectInterceptor : public net::URLRequest::Interceptor {
+class ConnectInterceptor : public net::URLRequestJobFactory::Interceptor {
  public:
   // Construction includes registration as an URL.
-  ConnectInterceptor();
+  explicit ConnectInterceptor(Predictor* predictor);
   // Destruction includes unregistering.
   virtual ~ConnectInterceptor();
 
  protected:
   // Overridden from net::URLRequest::Interceptor:
   // Learn about referrers, and optionally preconnect based on history.
-  virtual net::URLRequestJob* MaybeIntercept(net::URLRequest* request);
-  virtual net::URLRequestJob* MaybeInterceptResponse(net::URLRequest* request);
-  virtual net::URLRequestJob* MaybeInterceptRedirect(net::URLRequest* request,
-                                                     const GURL& location);
+  virtual net::URLRequestJob* MaybeIntercept(
+      net::URLRequest* request) const OVERRIDE;
+  virtual net::URLRequestJob* MaybeInterceptResponse(
+      net::URLRequest* request) const OVERRIDE;
+  virtual net::URLRequestJob* MaybeInterceptRedirect(
+      const GURL& location, net::URLRequest* request) const OVERRIDE;
 
  private:
   // Provide access to local class TimedCache for testing.
@@ -48,17 +53,20 @@
 
     // Evicts any entries that have been in the FIFO "too long," and then checks
     // to see if the given url is (still) in the FIFO cache.
-    bool WasRecentlySeen(const GURL& url);
+    bool WasRecentlySeen(const GURL& url) const;

[jar (doing other things), 2011/08/16 01:19:09]

Surprising to see const on a method that says it impacts the instance.  My guess
is that if it can be const, it is an artifact of the implementation, and should
not be exposed.

Was there some context where we really needed const (ref) instances, and you
wanted to allow that, ended up with the mutable declaration on line 69?

[rpetterson, 2011/08/16 03:52:12]

Yes, the new pattern is to sublass off of the UrlRequestFactory::Interceptor and
all of its methods are const. This seems to be the only case where we are
subclassing from it and run into this situation. The alternative was to alter
UrlRequestFactory::Interceptor which would would be a much more invasive change
so I opted to go with the mutable option you noted.

 
     // Adds the given url to the cache, where it will remain for max_duration_.
-    void SetRecentlySeen(const GURL& url);
+    void SetRecentlySeen(const GURL& url) const;
 
    private:
     // Our cache will be keyed on a URL (actually, just a scheme/host/port).
     // We will always track the time it was last added to the FIFO cache by
     // remembering a TimeTicks value.
     typedef base::MRUCache<GURL, base::TimeTicks> UrlMruTimedCache;
-    UrlMruTimedCache mru_cache_;
+    // mru_cache_ has to be mutable in order to be accessed from the overriden
+    // URLRequestJob functions. It is mutable because it tracks the urls and
+    // caches them.
+    mutable UrlMruTimedCache mru_cache_;
 
     // The longest time an entry can persist in the cache, and still be found.
     const base::TimeDelta max_duration_;
@@ -66,6 +74,7 @@
     DISALLOW_COPY_AND_ASSIGN(TimedCache);
   };
   TimedCache timed_cache_;
+  Predictor* predictor_;
 
   DISALLOW_COPY_AND_ASSIGN(ConnectInterceptor);
 };