Fix test-running in --single-process mode.

chrome/browser/profiles/profile_destroyer.cc

 // 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.
 
 #include "chrome/browser/profiles/profile_destroyer.h"
 
 #include "base/bind.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/message_loop.h"
 #include "chrome/browser/profiles/profile.h"
@@ skipping 17 matching lines @@
 
   std::vector<content::RenderProcessHost*> hosts;
   // Testing profiles can simply be deleted directly. Some tests don't setup
   // RenderProcessHost correctly and don't necessary run on the UI thread
   // anyway, so we can't use the AllHostIterator.
   if (profile->AsTestingProfile() == NULL) {
     GetHostsForProfile(profile, &hosts);
     if (!profile->IsOffTheRecord() && profile->HasOffTheRecordProfile())
       GetHostsForProfile(profile->GetOffTheRecordProfile(), &hosts);
   }
-  // This should never happen for non Off the record profile, this means that
-  // there is a leak in a render process host that MUST BE FIXED!!!
-  DCHECK(hosts.empty() || profile->IsOffTheRecord());
+  // Generally, !hosts.empty() means that there is a leak in a render process
+  // host that MUST BE FIXED!!!
+  //
+  // However, off-the-record profiles are destroyed before their
+  // RenderProcessHosts in order to erase private data quickly, and
+  // RenderProcessHostImpl::Release() avoids destroying RenderProcessHosts in
+  // --single-process mode to avoid race conditions.
+  DCHECK(hosts.empty() || profile->IsOffTheRecord() ||
+         content::RenderProcessHost::run_renderer_in_process());
   // Note that we still test for !profile->IsOffTheRecord here even though we
   // DCHECK'd above because we want to protect Release builds against this even
   // we need to identify if there are leaks when we run Debug builds.
   if (hosts.empty() || !profile->IsOffTheRecord()) {
     if (profile->IsOffTheRecord())
       profile->GetOriginalProfile()->DestroyOffTheRecordProfile();
     else
       delete profile;
   } else {
     // The instance will destroy itself once all render process hosts referring
@@ skipping 114 matching lines @@
         content::RenderProcessHost::AllHostsIterator());
       !iter.IsAtEnd(); iter.Advance()) {
     content::RenderProcessHost* render_process_host = iter.GetCurrentValue();
     if (render_process_host && Profile::FromBrowserContext(
           render_process_host->GetBrowserContext()) == profile) {
       hosts->push_back(render_process_host);
     }
   }
   return !hosts->empty();
 }