Implement NavigationThrottle::BLOCK_REQUEST_AND_COLLAPSE.

content/browser/frame_host/render_frame_host_manager.cc

Index: content/browser/frame_host/render_frame_host_manager.cc
diff --git a/content/browser/frame_host/render_frame_host_manager.cc b/content/browser/frame_host/render_frame_host_manager.cc
index cf4050b7eb81cb9e87dbac7cff8ff2ec48670e41..538adcac7814d3d754670681e6d5e34af61cff44 100644
--- a/content/browser/frame_host/render_frame_host_manager.cc
+++ b/content/browser/frame_host/render_frame_host_manager.cc
@@ -996,6 +996,27 @@ void RenderFrameHostManager::OnEnforceInsecureRequestPolicy(
   }
 }
 
+void RenderFrameHostManager::OnDidUpdateFrameOwnerCollapsedState(
+    bool collapsed) {
+  DCHECK(frame_tree_node_->parent());
+  SiteInstance* parent_site_instance =
+      frame_tree_node_->parent()->current_frame_host()->GetSiteInstance();
+
+  // There will be no proxy to represent the pending or speculative RFHs in the
+  // parent's site instance until the provisional load is committed, but the old
+  // RFH is not swapped out before that happens either, so we can talk to the
+  // FrameOwner in the parent via the child's current RenderFrame at any time.
+  DCHECK(current_frame_host());
+  if (current_frame_host()->GetSiteInstance() == parent_site_instance) {
+    current_frame_host()->Send(new FrameMsg_CollapseFrameOwner(
+        current_frame_host()->GetRoutingID(), collapsed));
+  } else {
+    RenderFrameProxyHost* proxy_to_parent = GetProxyToParent();
+    proxy_to_parent->Send(new FrameMsg_CollapseFrameOwner(
+        proxy_to_parent->GetRoutingID(), collapsed));
+  }
+}
+
 void RenderFrameHostManager::OnDidUpdateFrameOwnerProperties(
     const FrameOwnerProperties& properties) {
   if (!SiteIsolationPolicy::AreCrossProcessFramesPossible())