Fix memory leak in SiteInstance::CreateSiteInstanceForURL.

chrome/browser/tab_contents/site_instance.cc

 // 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.
 
 #include "chrome/browser/tab_contents/site_instance.h"
 
 #include "chrome/browser/renderer_host/browser_render_process_host.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/common/notification_service.h"
 #include "net/base/registry_controlled_domain.h"
@@ skipping 78 matching lines @@
 }
 
 /*static*/
 SiteInstance* SiteInstance::CreateSiteInstance(Profile* profile) {
   return new SiteInstance(new BrowsingInstance(profile));
 }
 
 /*static*/
 SiteInstance* SiteInstance::CreateSiteInstanceForURL(Profile* profile,
                                                      const GURL& url) {
-  return (new BrowsingInstance(profile))->GetSiteInstanceForURL(url);
+  // This BrowsingInstance may be deleted if it returns an existing
+  // SiteInstance.
+  scoped_refptr<BrowsingInstance> instance(new BrowsingInstance(profile));
+  return instance->GetSiteInstanceForURL(url);
 }
 
 /*static*/
 GURL SiteInstance::GetSiteForURL(const GURL& url) {
   // URLs with no host should have an empty site.
   GURL site;
 
   // TODO(creis): For many protocols, we should just treat the scheme as the
   // site, since there is no host.  e.g., file:, about:, chrome:
 
@@ skipping 59 matching lines @@
 }
 
 void SiteInstance::Observe(NotificationType type,
                            const NotificationSource& source,
                            const NotificationDetails& details) {
   DCHECK(type == NotificationType::RENDERER_PROCESS_TERMINATED);
   RenderProcessHost* rph = Source<RenderProcessHost>(source).ptr();
   if (rph == process_)
     process_ = NULL;
 }