Implement NavigationThrottle::BLOCK_REQUEST_AND_COLLAPSE.

content/browser/frame_host/frame_tree_node.cc

Index: content/browser/frame_host/frame_tree_node.cc
diff --git a/content/browser/frame_host/frame_tree_node.cc b/content/browser/frame_host/frame_tree_node.cc
index 0fadcaa8afb6208aa9e8cc06439e864a03a492eb..a1f00d37b9d10ed3198cb0e8c0e51544f685c7bd 100644
--- a/content/browser/frame_host/frame_tree_node.cc
+++ b/content/browser/frame_host/frame_tree_node.cc
@@ -106,6 +106,7 @@ FrameTreeNode::FrameTreeNode(FrameTree* frame_tree,
       original_opener_(nullptr),
       original_opener_observer_(nullptr),
       has_committed_real_load_(false),
+      is_collapsed_(false),
       replication_state_(
           scope,
           name,
@@ -260,6 +261,15 @@ void FrameTreeNode::SetCurrentOrigin(
       is_potentially_trustworthy_unique_origin;
 }
 
+void FrameTreeNode::SetCollapsed(bool collapsed) {
+  DCHECK(!IsMainFrame());
+  if (is_collapsed_ == collapsed)
+    return;
+
+  is_collapsed_ = collapsed;
+  render_manager_.OnDidChangeCollapsedState(collapsed);
+}
+
 void FrameTreeNode::SetFrameName(const std::string& name,
                                  const std::string& unique_name) {
   if (name == replication_state_.name) {