PlzNavigate: Get StreamPrivate API to work.

content/public/browser/web_contents.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_H_
 #define CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_H_
 
 #include <stdint.h>
 
 #include <set>
@@ skipping 168 matching lines @@
   CONTENT_EXPORT static WebContents* CreateWithSessionStorage(
       const CreateParams& params,
       const SessionStorageNamespaceMap& session_storage_namespace_map);
 
   // Returns the WebContents that owns the RenderViewHost, or nullptr if the
   // render view host's delegate isn't a WebContents.
   CONTENT_EXPORT static WebContents* FromRenderViewHost(RenderViewHost* rvh);
 
   CONTENT_EXPORT static WebContents* FromRenderFrameHost(RenderFrameHost* rfh);
 
+  // Returns the WebContents associated with the |frame_tree_node_id|.
+  CONTENT_EXPORT static WebContents* FromFrameTreeNodeId(
+      int frame_tree_node_id);
+
   ~WebContents() override {}
 
   // Intrinsic tab state -------------------------------------------------------
 
   // Gets/Sets the delegate.
   virtual WebContentsDelegate* GetDelegate() = 0;
   virtual void SetDelegate(WebContentsDelegate* delegate) = 0;
 
   // Gets the controller for this WebContents.
   virtual NavigationController& GetController() = 0;
@@ skipping 548 matching lines @@
 
  private:
   // This interface should only be implemented inside content.
   friend class WebContentsImpl;
   WebContents() {}
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_WEB_CONTENTS_H_