Fix race condition where chrome.tabs.executeScript sometimes wouldn't

chrome/renderer/navigation_state.cc

 // Copyright (c) 2010 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/renderer/navigation_state.h"
 
 #include "chrome/renderer/user_script_idle_scheduler.h"
 #include "webkit/glue/alt_error_page_resource_fetcher.h"
 #include "webkit/glue/password_form.h"
 
 NavigationState::~NavigationState() {}
 
 void NavigationState::set_user_script_idle_scheduler(
     UserScriptIdleScheduler* scheduler) {
   user_script_idle_scheduler_.reset(scheduler);
 }
 
+void NavigationState::swap_user_script_idle_scheduler(
+    NavigationState* state) {
+  user_script_idle_scheduler_.swap(state->user_script_idle_scheduler_);
+}
+
 void NavigationState::set_password_form_data(webkit_glue::PasswordForm* data) {
   password_form_data_.reset(data);
 }
 
 void NavigationState::set_alt_error_page_fetcher(
     webkit_glue::AltErrorPageResourceFetcher* f) {
   alt_error_page_fetcher_.reset(f);
 }
 
 NavigationState::NavigationState(PageTransition::Type transition_type,
@@ skipping 16 matching lines @@
       http_status_code_(0),
       was_fetched_via_spdy_(false),
       was_npn_negotiated_(false),
       was_alternate_protocol_available_(false),
       was_fetched_via_proxy_(false),
       was_translated_(false),
       was_within_same_page_(false),
       was_prefetcher_(false),
       was_referred_by_prefetcher_(false) {
 }