Move out DidStartProvisionalLoad from WebContentsImpl into Navigator.

content/content_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.
 
 {
   'dependencies': [
     'browser/speech/proto/speech_proto.gyp:speech_proto',
     '../base/base.gyp:base_static',
     '../crypto/crypto.gyp:crypto',
     '../google_apis/google_apis.gyp:google_apis',
@@ skipping 494 matching lines @@
     'browser/frame_host/frame_tree.h',
     'browser/frame_host/frame_tree_node.cc',
     'browser/frame_host/frame_tree_node.h',
     'browser/frame_host/interstitial_page_impl.cc',
     'browser/frame_host/interstitial_page_impl.h',
     'browser/frame_host/navigation_controller_delegate.h',
     'browser/frame_host/navigation_controller_impl.cc',
     'browser/frame_host/navigation_controller_impl.h',
     'browser/frame_host/navigation_entry_impl.cc',
     'browser/frame_host/navigation_entry_impl.h',
+    'browser/frame_host/navigator.cc',
+    'browser/frame_host/navigator.h',
+    'browser/frame_host/navigator_delegate.h',
     'browser/frame_host/render_frame_host_impl.cc',
     'browser/frame_host/render_frame_host_impl.h',
     'browser/frame_host/render_frame_message_filter.cc',
     'browser/frame_host/render_frame_message_filter.h',
     'browser/frame_host/render_view_host_manager.cc',
     'browser/frame_host/render_view_host_manager.h',
     'browser/frame_host/web_contents_screenshot_manager.cc',
     'browser/frame_host/web_contents_screenshot_manager.h',
     'browser/gamepad/gamepad_data_fetcher.h',
     'browser/gamepad/gamepad_platform_data_fetcher.h',
@@ skipping 1028 matching lines @@
         ['exclude', '^browser/speech/input_tag_speech_dispatcher_host\\.(cc|h)$'],
       ],
     }, {  # input_speech==1
       'dependencies': [
         '../third_party/flac/flac.gyp:libflac',
         '../third_party/speex/speex.gyp:libspeex',
       ],
     }],
   ],
 }