Make printing work better with OOPIF.

content/public/renderer/render_frame_observer.h

 // Copyright 2013 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_RENDERER_RENDER_FRAME_OBSERVER_H_
 #define CONTENT_PUBLIC_RENDERER_RENDER_FRAME_OBSERVER_H_
 
 #include <stdint.h>
 
 #include "base/compiler_specific.h"
@@ skipping 104 matching lines @@
   // load. This is used for metrics collection.
   virtual void DidObserveLoadingBehavior(
       blink::WebLoadingBehaviorFlag behavior) {}
 
   // Called when the focused node has changed to |node|.
   virtual void FocusedNodeChanged(const blink::WebNode& node) {}
 
   // Called when accessibility is enabled or disabled.
   virtual void AccessibilityModeChanged() {}
 
+  // For printing.
+  virtual void ScriptedPrint(bool user_initiated) {}
+  virtual void DidStartLoading() {}

[nasko, 2016/10/27 20:26:26]

Let's not add this, as Start/Stop Loading is global for the full page, which
isn't per frame.
DidStartLoading can be replaced by DidStartProvisionalLoad.
DidStopLoading can be replaced by combo of DidFailProvisionalLoad for failure
case and DidFinishLoad for the success case.

[Lei Zhang, 2016/10/28 23:27:10]

Done.

+  virtual void DidStopLoading() {}
+
   // IPC::Listener implementation.
   bool OnMessageReceived(const IPC::Message& message) override;
 
   // IPC::Sender implementation.
   bool Send(IPC::Message* message) override;
 
   RenderFrame* render_frame() const;
   int routing_id() const { return routing_id_; }
 
  protected:
@@ skipping 10 matching lines @@
   RenderFrame* render_frame_;
   // The routing ID of the associated RenderFrame.
   int routing_id_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderFrameObserver);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_RENDERER_RENDER_FRAME_OBSERVER_H_