[subresource_filter] Remove some state from the driver factory

chrome/browser/page_load_metrics/observers/subresource_filter_metrics_observer.cc

 // Copyright 2017 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/page_load_metrics/observers/subresource_filter_metrics_observer.h"
 
 #include "chrome/browser/page_load_metrics/page_load_metrics_util.h"
 #include "components/subresource_filter/content/browser/content_subresource_filter_driver_factory.h"
+#include "components/subresource_filter/content/browser/content_subresource_filter_throttle_manager.h"
+#include "components/subresource_filter/core/common/activation_decision.h"
 #include "third_party/WebKit/public/platform/WebLoadingBehaviorFlag.h"
 
 using subresource_filter::ContentSubresourceFilterDriverFactory;
 
-using ActivationDecision = subresource_filter::
-    ContentSubresourceFilterDriverFactory::ActivationDecision;
+using ActivationDecision = subresource_filter::ActivationDecision;
 
 namespace internal {
 
 const char kHistogramSubresourceFilterFirstContentfulPaint[] =
     "PageLoad.Clients.SubresourceFilter.PaintTiming."
     "NavigationToFirstContentfulPaint";
 const char kHistogramSubresourceFilterParseStartToFirstContentfulPaint[] =
     "PageLoad.Clients.SubresourceFilter.PaintTiming."
     "ParseStartToFirstContentfulPaint";
 const char kHistogramSubresourceFilterFirstMeaningfulPaint[] =
@@ skipping 125 matching lines @@
 
 page_load_metrics::PageLoadMetricsObserver::ObservePolicy
 SubresourceFilterMetricsObserver::OnCommit(
     content::NavigationHandle* navigation_handle) {
   const auto* subres_filter =
       ContentSubresourceFilterDriverFactory::FromWebContents(
           navigation_handle->GetWebContents());
   if (subres_filter)
     LogActivationDecisionMetrics(
         navigation_handle,
-        subres_filter->GetActivationDecisionForLastCommittedPageLoad());
+        subres_filter->throttle_manager()

[engedy, 2017/04/27 13:59:52]

I can see two somewhat acceptable options here (read my overall comments first):

 -- Keep the semantics of this method as is, but add enough delay here to make
sure we are not calling methods named `...ForLastCommittedPageLoad` until after
the page load really has been committed. :-)

 -- Store the |activation_decison| on the SafeBrowsingActivationThrottle so that
it can be accessed anytime after ReadyToCommit. Retrieve the throttle here from
the ContentSubresourceFilterDriverFactory replacement in exchange for giving it
the |navigation_handle|.

I think the second would be the nicer solution.

+            ->GetActivationDecisionForLastCommittedPageLoad());
   return CONTINUE_OBSERVING;
 }
 
 void SubresourceFilterMetricsObserver::OnComplete(
     const page_load_metrics::PageLoadTiming& timing,
     const page_load_metrics::PageLoadExtraInfo& info) {
   OnGoingAway(timing, info, base::TimeTicks());
 }
 
 void SubresourceFilterMetricsObserver::OnLoadedResource(
@@ skipping 194 matching lines @@
         foreground_duration.value());
     if (timing.paint_timing.first_paint &&
         timing.paint_timing.first_paint < foreground_duration) {
       PAGE_LOAD_LONG_HISTOGRAM(
           internal::kHistogramSubresourceFilterForegroundDurationAfterPaint,
           foreground_duration.value() -
               timing.paint_timing.first_paint.value());
     }
   }
 }