PlzNavigate: identify same-page browser-initiated navigation.

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 a67de695a205b85c456d5c8f63254140222ec10f..fa986781bdbfbbd59ba56434e9a5ff7dbdead7ee 100644
--- a/content/browser/frame_host/frame_tree_node.cc
+++ b/content/browser/frame_host/frame_tree_node.cc
@@ -363,9 +363,11 @@ void FrameTreeNode::CreatedNavigationRequest(
   navigation_request_ = std::move(navigation_request);
   render_manager()->DidCreateNavigationRequest(navigation_request_.get());
 
-  // TODO(fdegans): Check if this is a same-document navigation and set the
-  // proper argument.
-  DidStartLoading(true, was_previously_loading);
+  bool is_same_document =
+      navigation_request_->request_params().is_same_document_fragment_change ||
+      navigation_request_->request_params().is_same_document_history_load;
+
+  DidStartLoading(!is_same_document, was_previously_loading);
 }
 
 void FrameTreeNode::ResetNavigationRequest(bool keep_state) {