Detect when chrome is shutting down and don't SendFinacialPing

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 563 matching lines @@
       base::Bind(&RLZTracker::ClearRlzStateImpl,
                  base::Unretained(this)));
   return true;
 }
 #endif
 
 // static
 void RLZTracker::CleanupRlz() {
   GetInstance()->rlz_cache_.clear();
   GetInstance()->registrar_.RemoveAll();
+  rlz_lib::SetURLRequestContext(NULL);
 }
 
 // static
 void RLZTracker::EnableZeroDelayForTesting() {
   GetInstance()->min_init_delay_ = base::TimeDelta();
 }