Move unload handling off Browser onto its own class, UnloadController.

chrome/chrome_browser.gypi

 # 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.
 
 {
   'targets': [
     {
       'target_name': 'browser',
       'type': 'static_library',
@@ skipping 3399 matching lines @@
         'browser/ui/toolbar/bookmark_sub_menu_model.cc',
         'browser/ui/toolbar/bookmark_sub_menu_model.h',
         'browser/ui/toolbar/encoding_menu_controller.cc',
         'browser/ui/toolbar/encoding_menu_controller.h',
         'browser/ui/toolbar/toolbar_model.cc',
         'browser/ui/toolbar/toolbar_model.h',
         'browser/ui/toolbar/toolbar_model_delegate.h',
         'browser/ui/toolbar/wrench_menu_model.cc',
         'browser/ui/toolbar/wrench_menu_model.h',
         'browser/ui/uninstall_browser_prompt.h',
+        'browser/ui/unload_controller.cc',
+        'browser/ui/unload_controller.h',
         'browser/ui/user_data_dir_dialog.h',
         'browser/ui/view_ids.h',
         'browser/ui/views/about_chrome_view.cc',
         'browser/ui/views/about_chrome_view.h',
         'browser/ui/views/about_ipc_dialog.cc',
         'browser/ui/views/about_ipc_dialog.h',
         'browser/ui/views/accelerator_table.cc',
         'browser/ui/views/accelerator_table.h',
         'browser/ui/views/accessibility/accessibility_event_router_views.cc',
         'browser/ui/views/accessibility/accessibility_event_router_views.h',
@@ skipping 1936 matching lines @@
         'browser/metrics/proto/study.proto',
       ],
       'variables': {
         'proto_in_dir': 'browser/metrics/proto',
         'proto_out_dir': 'chrome/browser/metrics/proto',
       },
       'includes': [ '../build/protoc.gypi' ]
     },
   ],
 }