Add a referrer class to be used in the browser process whenever passing around referrsr

content/content_browser.gypi

 # Copyright (c) 2011 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.
 
 {
   'dependencies': [
     '../crypto/crypto.gyp:crypto',
     '../net/net.gyp:net',
     '../net/net.gyp:http_server',
     '../ppapi/ppapi_internal.gyp:ppapi_proxy',
@@ skipping 533 matching lines @@
     'browser/tab_contents/navigation_details.cc',
     'browser/tab_contents/navigation_details.h',
     'browser/tab_contents/navigation_entry.cc',
     'browser/tab_contents/navigation_entry.h',
     'browser/tab_contents/page_navigator.cc',
     'browser/tab_contents/page_navigator.h',
     'browser/tab_contents/popup_menu_helper_mac.h',
     'browser/tab_contents/popup_menu_helper_mac.mm',
     'browser/tab_contents/provisional_load_details.cc',
     'browser/tab_contents/provisional_load_details.h',
+    'browser/tab_contents/referrer.cc',
+    'browser/tab_contents/referrer.h',
     'browser/tab_contents/render_view_host_manager.cc',
     'browser/tab_contents/render_view_host_manager.h',
     'browser/tab_contents/tab_contents.cc',
     'browser/tab_contents/tab_contents.h',
     'browser/tab_contents/tab_contents_delegate.cc',
     'browser/tab_contents/tab_contents_delegate.h',
     'browser/tab_contents/tab_contents_observer.cc',
     'browser/tab_contents/tab_contents_observer.h',
     'browser/tab_contents/tab_contents_view.cc',
     'browser/tab_contents/tab_contents_view.h',
@@ skipping 227 matching lines @@
         'browser/renderer_host/java/java_bridge_dispatcher_host_manager.h',
         'browser/renderer_host/java/java_bridge_dispatcher_host.cc',
         'browser/renderer_host/java/java_bridge_dispatcher_host.h',
         'browser/renderer_host/java/java_method.cc',
         'browser/renderer_host/java/java_method.h',
       ],
     }],
   ],
 }