[subresource_filter] Reland: Remove Forwarding NavigationThrottles

content/public/test/navigation_simulator.cc

Index: content/public/test/navigation_simulator.cc
diff --git a/content/public/test/navigation_simulator.cc b/content/public/test/navigation_simulator.cc
index bf2995e4f2fdf17b6ab95c23b02c56dfe4fd1112..5b12daabdb34c761cf77284a48e02981e97e5972 100644
--- a/content/public/test/navigation_simulator.cc
+++ b/content/public/test/navigation_simulator.cc
@@ -483,6 +483,11 @@ NavigationSimulator::GetLastThrottleCheckResult() {
   return last_throttle_check_result_.value();
 }
 
+NavigationHandle* NavigationSimulator::GetNavigationHandle() const {
+  CHECK_EQ(STARTED, state_);
+  return handle_;
+}
+
 void NavigationSimulator::DidStartNavigation(
     NavigationHandle* navigation_handle) {
   // Check if this navigation is the one we're simulating.