system_request_context() has to be called on the UI thread.

chrome/browser/rlz/rlz.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.
 //
 // This code glues the RLZ library DLL with Chrome. It allows Chrome to work
 // with or without the DLL being present. If the DLL is not present the
 // functions do nothing and just return false.
 
 #include "chrome/browser/rlz/rlz.h"
 
@@ skipping 175 matching lines @@
   // If instant is enabled we'll start searching as soon as the user starts
   // typing in the omnibox (which triggers INSTANT_CONTROLLER_UPDATED).
   registrar_.Add(this, chrome::NOTIFICATION_INSTANT_CONTROLLER_UPDATED,
                  content::NotificationService::AllSources());
 
   // Register for notifications from navigations, to see if the user has used
   // the home page.
   registrar_.Add(this, content::NOTIFICATION_NAV_ENTRY_PENDING,
                  content::NotificationService::AllSources());
 
+  rlz_lib::SetURLRequestContext(g_browser_process->system_request_context());
   ScheduleDelayedInit(delay);
 
   return true;
 }
 
 void RLZTracker::ScheduleDelayedInit(int delay) {
   // The RLZTracker is a singleton object that outlives any runnable tasks
   // that will be queued up.
   // TODO: Move to SequencedWorkerPool once http://crbug.com/119657 is fixed.
   BrowserThread::PostDelayedTask(
       BrowserThread::FILE,
       FROM_HERE,
       base::Bind(&RLZTracker::DelayedInit, base::Unretained(this)),
       delay);
 }
 
 void RLZTracker::DelayedInit() {
   worker_pool_token_ = BrowserThread::GetBlockingPool()->GetSequenceToken();
 
   bool schedule_ping = false;
 
-  rlz_lib::SetURLRequestContext(g_browser_process->system_request_context());
-
   // For organic brandcodes do not use rlz at all. Empty brandcode usually
   // means a chromium install. This is ok.
   std::string brand;
   if (google_util::GetBrand(&brand) && !IsBrandOrganic(brand)) {
     RecordProductEvents(first_run_, google_default_search_,
                         google_default_homepage_, already_ran_,
                         omnibox_used_, homepage_used_);
     schedule_ping = true;
   }
 
@@ skipping 178 matching lines @@
       base::Bind(base::IgnoreResult(&RLZTracker::GetAccessPointRlz), point,
                  not_used));
   return true;
 }
 
 // static
 void RLZTracker::CleanupRlz() {
   GetInstance()->rlz_cache_.clear();
   GetInstance()->registrar_.RemoveAll();
 }