Implement NavigationThrottle::BLOCK_REQUEST_AND_COLLAPSE.

content/browser/frame_host/navigation_request.cc

Index: content/browser/frame_host/navigation_request.cc
diff --git a/content/browser/frame_host/navigation_request.cc b/content/browser/frame_host/navigation_request.cc
index 895d3891a6ca6662039bd1f7a5bf949729ed204b..3597e982d8a6c14272ea274d03b31f7668640c05 100644
--- a/content/browser/frame_host/navigation_request.cc
+++ b/content/browser/frame_host/navigation_request.cc
@@ -568,7 +568,8 @@ void NavigationRequest::OnStartChecksComplete(
     return;
   }
 
-  if (result == NavigationThrottle::BLOCK_REQUEST) {
+  if (result == NavigationThrottle::BLOCK_REQUEST ||
+      result == NavigationThrottle::BLOCK_REQUEST_AND_COLLAPSE) {
     OnRequestFailed(false, net::ERR_BLOCKED_BY_CLIENT);
     // DO NOT ADD CODE after this. The previous call to OnRequestFailed has
     // destroyed the NavigationRequest.
@@ -655,8 +656,10 @@ void NavigationRequest::OnRedirectChecksComplete(
 
   // Abort the request if needed. This will destroy the NavigationRequest.
   if (result == NavigationThrottle::CANCEL_AND_IGNORE ||
-      result == NavigationThrottle::CANCEL) {
-    // TODO(clamy): distinguish between CANCEL and CANCEL_AND_IGNORE.
+      result == NavigationThrottle::CANCEL ||
+      result == NavigationThrottle::BLOCK_REQUEST_AND_COLLAPSE) {
+    // TODO(clamy): distinguish between CANCEL and CANCEL_AND_IGNORE,
+    // as well as BLOCK_REQUEST_AND_COLLAPSE if needed.
     frame_tree_node_->ResetNavigationRequest(false);
     return;
   }