[subresource_filter] Add metrics for all NavigationThrottle delays

components/subresource_filter/content/browser/subframe_navigation_filtering_throttle.cc

Index: components/subresource_filter/content/browser/subframe_navigation_filtering_throttle.cc
diff --git a/components/subresource_filter/content/browser/subframe_navigation_filtering_throttle.cc b/components/subresource_filter/content/browser/subframe_navigation_filtering_throttle.cc
index 020b42f8bf4d5e85601f6447fe5b3c873804a383..ebb562e5278a6f19584c350ea235efd6285956b8 100644
--- a/components/subresource_filter/content/browser/subframe_navigation_filtering_throttle.cc
+++ b/components/subresource_filter/content/browser/subframe_navigation_filtering_throttle.cc
@@ -6,6 +6,8 @@
 
 #include "base/bind.h"
 #include "base/logging.h"
+#include "base/metrics/histogram_macros.h"
+#include "components/subresource_filter/core/common/time_measurements.h"
 #include "content/public/browser/navigation_handle.h"
 
 namespace subresource_filter {
@@ -20,7 +22,19 @@ SubframeNavigationFilteringThrottle::SubframeNavigationFilteringThrottle(
   DCHECK(parent_frame_filter_);
 }
 
-SubframeNavigationFilteringThrottle::~SubframeNavigationFilteringThrottle() {}
+SubframeNavigationFilteringThrottle::~SubframeNavigationFilteringThrottle() {
+  if (disallowed_) {
+    UMA_HISTOGRAM_CUSTOM_MICRO_TIMES(
+        "SubresourceFilter.DocumentLoad.SubframeFilteringDelay.Disallowed",
+        total_defer_time_, base::TimeDelta::FromMicroseconds(1),
+        base::TimeDelta::FromSeconds(10), 50);
+  } else {
+    UMA_HISTOGRAM_CUSTOM_MICRO_TIMES(
+        "SubresourceFilter.DocumentLoad.SubframeFilteringDelay.Allowed",
+        total_defer_time_, base::TimeDelta::FromMicroseconds(1),
+        base::TimeDelta::FromSeconds(10), 50);
+  }
+}
 
 content::NavigationThrottle::ThrottleCheckResult
 SubframeNavigationFilteringThrottle::WillStartRequest() {
@@ -42,14 +56,18 @@ SubframeNavigationFilteringThrottle::DeferToCalculateLoadPolicy() {
       navigation_handle()->GetURL(),
       base::Bind(&SubframeNavigationFilteringThrottle::OnCalculatedLoadPolicy,
                  weak_ptr_factory_.GetWeakPtr()));
+  last_defer_timestamp_ = base::TimeTicks::Now();
   return content::NavigationThrottle::ThrottleCheckResult::DEFER;
 }
 
 void SubframeNavigationFilteringThrottle::OnCalculatedLoadPolicy(
     LoadPolicy policy) {
+  DCHECK(!last_defer_timestamp_.is_null());
+  total_defer_time_ += base::TimeTicks::Now() - last_defer_timestamp_;
   // TODO(csharrison): Support WouldDisallow pattern and expose the policy for
   // metrics. Also, cancel with BLOCK_AND_COLLAPSE when it is implemented.
   if (policy == LoadPolicy::DISALLOW) {
+    disallowed_ = true;
     parent_frame_filter_->ReportDisallowedLoad();
     navigation_handle()->CancelDeferredNavigation(
         content::NavigationThrottle::CANCEL);