Adds a unit test for NavigationEntry. Also adds a comment to BrowsingInstanc...

chrome/browser/browsing_instance.h

 // Copyright (c) 2006-2008 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_BROWSING_INSTANCE_H__
 #define CHROME_BROWSER_BROWSING_INSTANCE_H__
 
 #include "base/hash_tables.h"
 #include "chrome/browser/profile.h"
 #include "googleurl/src/gurl.h"
@@ skipping 27 matching lines @@
 // (This is currently only true if --process-per-site is specified at the
 // command line.)
 //
 // A BrowsingInstance is live as long as any SiteInstance has a reference to
 // it.  A SiteInstance is live as long as any NavigationEntry or RenderViewHost
 // have references to it.  Because both classes are RefCounted, they do not
 // need to be manually deleted.
 //
 // Currently, the BrowsingInstance class is not visible outside of the
 // SiteInstance class.  To get a new SiteInstance that is part of the same
-// BrowsingInstance, use SiteInstance::GetRelatedSiteInstance.
+// BrowsingInstance, use SiteInstance::GetRelatedSiteInstance.  Because of
+// this, BrowsingInstances and SiteInstances are tested together in
+// site_instance_unittest.cc.
 //
 ///////////////////////////////////////////////////////////////////////////////
 class BrowsingInstance : public base::RefCounted<BrowsingInstance> {
  public:
   // Create a new BrowsingInstance.
   BrowsingInstance(Profile* profile)
       : profile_(profile) {
   }
 
   // Virtual to allow tests to extend it.
@@ skipping 60 matching lines @@
   // This field is only used if we are not using process-per-site.
   SiteInstanceMap site_instance_map_;
 
   // Global map of Profile to SiteInstanceMap, for process-per-site.
   static ProfileSiteInstanceMap profile_site_instance_map_;
 
   DISALLOW_EVIL_CONSTRUCTORS(BrowsingInstance);
 };
 
 #endif  //  CHROME_BROWSER_BROWSING_INSTANCE_H__