Implement NavigationThrottle::BLOCK_REQUEST_AND_COLLAPSE.

content/browser/loader/navigation_resource_throttle.cc

Index: content/browser/loader/navigation_resource_throttle.cc
diff --git a/content/browser/loader/navigation_resource_throttle.cc b/content/browser/loader/navigation_resource_throttle.cc
index 6a7f6b6688ed16a84c9d65a217ecfba6a8e24d05..848bd0e3bc9aaad55a8c29b4485917a03cfc9ec0 100644
--- a/content/browser/loader/navigation_resource_throttle.cc
+++ b/content/browser/loader/navigation_resource_throttle.cc
@@ -348,7 +348,8 @@ void NavigationResourceThrottle::OnUIChecksPerformed(
     CancelAndIgnore();
   } else if (result == NavigationThrottle::CANCEL) {
     Cancel();
-  } else if (result == NavigationThrottle::BLOCK_REQUEST) {
+  } else if (result == NavigationThrottle::BLOCK_REQUEST ||
+             result == NavigationThrottle::BLOCK_REQUEST_AND_COLLAPSE) {
     CancelWithError(net::ERR_BLOCKED_BY_CLIENT);
   } else if (result == NavigationThrottle::BLOCK_RESPONSE) {
     // TODO(mkwst): If we cancel the main frame request with anything other than