[Downloads] Rework how hashes are calculated for download files.

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': [
     '../base/base.gyp:base_static',
     '../cc/cc.gyp:cc',
     '../cc/cc.gyp:cc_surfaces',
     '../components/mime_util/mime_util.gyp:mime_util',
@@ skipping 146 matching lines @@
       'public/browser/desktop_media_id.h',
       'public/browser/desktop_notification_delegate.h',
       'public/browser/devtools_agent_host.h',
       'public/browser/devtools_agent_host_client.h',
       'public/browser/devtools_external_agent_proxy.h',
       'public/browser/devtools_external_agent_proxy_delegate.h',
       'public/browser/devtools_frontend_host.h',
       'public/browser/devtools_manager_delegate.h',
       'public/browser/dom_storage_context.h',
       'public/browser/download_danger_type.h',
-      'public/browser/download_destination_observer.h',
       'public/browser/download_interrupt_reason_values.h',
       'public/browser/download_interrupt_reasons.h',
       'public/browser/download_item.h',
       'public/browser/download_manager.h',
       'public/browser/download_manager_delegate.cc',
       'public/browser/download_manager_delegate.h',
       'public/browser/download_save_info.cc',
       'public/browser/download_save_info.h',
       'public/browser/download_url_parameters.cc',
       'public/browser/download_url_parameters.h',
@@ skipping 475 matching lines @@
       'browser/dom_storage/session_storage_namespace_impl.cc',
       'browser/dom_storage/session_storage_namespace_impl.h',
       'browser/download/base_file.cc',
       'browser/download/base_file.h',
       'browser/download/base_file_linux.cc',
       'browser/download/base_file_mac.cc',
       'browser/download/base_file_posix.cc',
       'browser/download/base_file_win.cc',
       'browser/download/download_create_info.cc',
       'browser/download/download_create_info.h',
+      'browser/download/download_destination_observer.h',
       'browser/download/download_file.h',
       'browser/download/download_file_factory.cc',
       'browser/download/download_file_factory.h',
       'browser/download/download_file_impl.cc',
       'browser/download/download_file_impl.h',
       'browser/download/download_interrupt_reasons_impl.cc',
       'browser/download/download_interrupt_reasons_impl.h',
       'browser/download/download_item_factory.h',
       'browser/download/download_item_impl.cc',
       'browser/download/download_item_impl.h',
@@ skipping 1519 matching lines @@
     ['enable_webvr==1 and OS=="android"', {
       'sources': [
         'browser/vr/android/cardboard/cardboard_vr_device.cc',
         'browser/vr/android/cardboard/cardboard_vr_device.h',
         'browser/vr/android/cardboard/cardboard_vr_device_provider.cc',
         'browser/vr/android/cardboard/cardboard_vr_device_provider.h',
       ],
     }],
   ],
 }