PPAPI: Get TrackedCallback ready for running on non-main threads.

ppapi/shared_impl/private/ppb_host_resolver_shared.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 "ppapi/shared_impl/private/ppb_host_resolver_shared.h"
 
 #include <cstddef>
 #include <cstring>
 
 #include "base/memory/scoped_ptr.h"
@@ skipping 66 matching lines @@
     const std::string& canonical_name,
     const std::vector<PP_NetAddress_Private>& net_address_list) {
   if (succeeded) {
     canonical_name_ = canonical_name;
     net_address_list_ = net_address_list;
   } else {
     canonical_name_.clear();
     net_address_list_.clear();
   }
 
-  TrackedCallback::ClearAndRun(&resolve_callback_,
-                               succeeded ? PP_OK : PP_ERROR_FAILED);
+  resolve_callback_->Run(succeeded ? PP_OK : PP_ERROR_FAILED);
 }
 
 uint32 PPB_HostResolver_Shared::GenerateHostResolverID() {
   static uint32 host_resolver_id = 0;
   return host_resolver_id++;
 }
 
 bool PPB_HostResolver_Shared::ResolveInProgress() const {
   return TrackedCallback::IsPending(resolve_callback_);
 }
 
 }  // namespace ppapi