Tracing for NavigationHandle lifetime and state.

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 4fa61169d4b655f2ac8757f476fde8aa5ed55df2..020b42f8bf4d5e85601f6447fe5b3c873804a383 100644
--- a/components/subresource_filter/content/browser/subframe_navigation_filtering_throttle.cc
+++ b/components/subresource_filter/content/browser/subframe_navigation_filtering_throttle.cc
@@ -32,6 +32,10 @@ SubframeNavigationFilteringThrottle::WillRedirectRequest() {
   return DeferToCalculateLoadPolicy();
 }
 
+const char* SubframeNavigationFilteringThrottle::GetNameForLogging() {
+  return "SubframeNavigationFilteringThrottle";
+}
+
 content::NavigationThrottle::ThrottleCheckResult
 SubframeNavigationFilteringThrottle::DeferToCalculateLoadPolicy() {
   parent_frame_filter_->GetLoadPolicyForSubdocument(