First experimental implementation of the Clear-Site-Data header

chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.cc

 // 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.
 
 #include "chrome/browser/renderer_host/chrome_resource_dispatcher_host_delegate.h"
 
 #include <stdint.h>
 #include <string>
 #include <utility>
 #include <vector>
 
 #include "base/base64.h"
 #include "base/guid.h"
 #include "base/logging.h"
 #include "base/metrics/field_trial.h"
 #include "base/metrics/histogram_macros.h"
 #include "base/strings/string_util.h"
 #include "build/build_config.h"
 #include "chrome/browser/browser_process.h"
+#include "chrome/browser/browsing_data/clear_site_data_throttle.h"

[Mike West, 2016/05/31 05:35:52]

All the throttle machinery should be in //content, not //chrome (because this is
a ~standardized, web-facing API). See
`//content/browser/frame_host/navigation_handle_impl.cc` in
https://codereview.chromium.org/1617043002/ for an example of what that might
look like.

[msramek, 2016/06/01 14:20:41]

Done. Moved to content. It actually made some things easier (no more jumping
around threads needed now).

 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/component_updater/component_updater_resource_throttle.h"
 #include "chrome/browser/download/download_request_limiter.h"
 #include "chrome/browser/download/download_resource_throttle.h"
 #include "chrome/browser/mod_pagespeed/mod_pagespeed_metrics.h"
 #include "chrome/browser/net/resource_prefetch_predictor_observer.h"
 #include "chrome/browser/plugins/plugin_prefs.h"
 #include "chrome/browser/prerender/prerender_manager.h"
 #include "chrome/browser/prerender/prerender_manager_factory.h"
 #include "chrome/browser/prerender/prerender_resource_throttle.h"
@@ skipping 581 matching lines @@
   }
 #endif
 
   const ResourceRequestInfo* info = ResourceRequestInfo::ForRequest(request);
   if (info->GetVisibilityState() == blink::WebPageVisibilityStatePrerender) {
     throttles->push_back(new prerender::PrerenderResourceThrottle(request));
   }
 
   if (ThreadHopResourceThrottle::IsEnabled())
     throttles->push_back(new ThreadHopResourceThrottle);
+
+  // Experimental Clear-Site-Data throttle. Create only for the main frame.

[Mike West, 2016/05/31 05:35:52]

This is fine to start with, but an eventual goal should probably be to support
various kinds of requests, not just navigations. See
https://w3c.github.io/webappsec-clear-site-data/#example-targeted, for example.
We should either decide not to support that use case, or come up with a plan for
eventually adding it in.

[msramek, 2016/06/01 14:20:41]

I removed the condition for now. My intention was not to contradict the spec,
but to limit the impact in the early experimentation stage.

+  if (resource_type == content::RESOURCE_TYPE_MAIN_FRAME)
+    throttles->push_back(new ClearSiteDataThrottle(request));
 }
 
 bool ChromeResourceDispatcherHostDelegate::ShouldForceDownloadResource(
     const GURL& url, const std::string& mime_type) {
 #if defined(ENABLE_EXTENSIONS)
   // Special-case user scripts to get downloaded instead of viewed.
   return extensions::UserScript::IsURLUserScript(url, mime_type);
 #else
   return false;
 #endif
@@ skipping 206 matching lines @@
   data_reduction_proxy::DataReductionProxyData* data_reduction_proxy_data =
       data_reduction_proxy::DataReductionProxyData::GetData(*request);
   // DeepCopy the DataReductionProxyData from the URLRequest to prevent the
   // URLRequest and DataReductionProxyData from both having ownership of the
   // same object. This copy will be shortlived as it will be deep copied again
   // when content makes a clone of NavigationData for the UI thread.
   if (data_reduction_proxy_data)
     data->SetDataReductionProxyData(data_reduction_proxy_data->DeepCopy());
   return data;
 }