PlzNavigate: Add a static CommitNavigation method in FrameTreeNode

content/browser/frame_host/frame_tree.h

Index: content/browser/frame_host/frame_tree.h
diff --git a/content/browser/frame_host/frame_tree.h b/content/browser/frame_host/frame_tree.h
index 5e58562a87912a98b2439aa872614d7f3a5a46a7..a4471a46376b5b15b63fe10c5a3ca6fe0ab94dd4 100644
--- a/content/browser/frame_host/frame_tree.h
+++ b/content/browser/frame_host/frame_tree.h
@@ -22,6 +22,7 @@ class RenderViewHostDelegate;
 class RenderViewHostImpl;
 class RenderFrameHostManager;
 class RenderWidgetHostDelegate;
+struct NavigationBeforeCommitInfo;
 
 // Represents the frame tree for a page. With the exception of the main frame,
 // all FrameTreeNodes will be created/deleted in response to frame attach and
@@ -50,6 +51,13 @@ class CONTENT_EXPORT FrameTree {
             RenderFrameHostManager::Delegate* manager_delegate);
   ~FrameTree();
 
+  // PlzNavigate
+  // Signal the node with id |frame_tree_node_id| that a navigation request is
+  // ready to commit.
+  static void CommitNavigationInNode(int64 frame_tree_node_id,
+                                     const NavigationBeforeCommitInfo& info);
+
+
   FrameTreeNode* root() const { return root_.get(); }
 
   // Returns the FrameTreeNode with the given |frame_tree_node_id|.