Ensure FrameNavigationEntry is fully updated.

content/browser/frame_host/navigation_entry_impl.cc

Index: content/browser/frame_host/navigation_entry_impl.cc
diff --git a/content/browser/frame_host/navigation_entry_impl.cc b/content/browser/frame_host/navigation_entry_impl.cc
index 41033a819a689111868c496c1755a18fca585830..e2cdcb8bcebd8b39ac46b4c4da6811530cbc598c 100644
--- a/content/browser/frame_host/navigation_entry_impl.cc
+++ b/content/browser/frame_host/navigation_entry_impl.cc
@@ -774,9 +774,33 @@ void NavigationEntryImpl::AddOrUpdateFrameEntry(
     const PageState& page_state,
     const std::string& method,
     int64_t post_id) {
+  // We should only have an empty PageState if the navigation is new, and thus
+  // page ID is -1.
+  if (!page_state.IsValid() && GetPageID() != -1) {
+    // Temporarily generate a minidump to diagnose https://crbug.com/568703.
+    base::debug::DumpWithoutCrashing();
+    NOTREACHED() << "Shouldn't set an empty PageState.";
+  }
+
+  // If this is called for the main frame, the FrameNavigationEntry is
+  // guaranteed to exist, so just update it directly and return.
+  if (frame_tree_node->IsMainFrame()) {
+    // If the document of the FrameNavigationEntry is changing, we must clear
+    // any child FrameNavigationEntries.
+    if (root_node()->frame_entry->document_sequence_number() !=
+        document_sequence_number)
+      root_node()->children.clear();
+
+    root_node()->frame_entry->UpdateEntry(
+        frame_tree_node->unique_name(), item_sequence_number,
+        document_sequence_number, site_instance,
+        std::move(source_site_instance), url, referrer, page_state, method,
+        post_id);
+    return;
+  }
+
   // We should already have a TreeNode for the parent node by the time this node
   // commits.  Find it first.
-  DCHECK(frame_tree_node->parent());
   NavigationEntryImpl::TreeNode* parent_node =
       FindFrameEntry(frame_tree_node->parent());
   if (!parent_node) {
@@ -785,14 +809,6 @@ void NavigationEntryImpl::AddOrUpdateFrameEntry(
     return;
   }
 
-  // We should only have an empty PageState if the navigation is new, and thus
-  // page ID is -1.
-  if (!page_state.IsValid() && GetPageID() != -1) {
-    // Temporarily generate a minidump to diagnose https://crbug.com/568703.
-    base::debug::DumpWithoutCrashing();
-    NOTREACHED() << "Shouldn't set an empty PageState.";
-  }
-
   // Now check whether we have a TreeNode for the node itself.
   const std::string& unique_name = frame_tree_node->unique_name();
   for (TreeNode* child : parent_node->children) {
@@ -830,12 +846,6 @@ FrameNavigationEntry* NavigationEntryImpl::GetFrameEntry(
   return tree_node ? tree_node->frame_entry.get() : nullptr;
 }
 
-void NavigationEntryImpl::ClearChildren(FrameTreeNode* frame_tree_node) {
-  NavigationEntryImpl::TreeNode* tree_node = FindFrameEntry(frame_tree_node);
-  if (tree_node)
-    tree_node->children.clear();
-}
-
 void NavigationEntryImpl::ClearStaleFrameEntriesForNewFrame(
     FrameTreeNode* frame_tree_node) {
   DCHECK(!frame_tree_node->IsMainFrame());