Implement PrintBrowser functionality.

chrome/browser/printing/print_preview_message_handler.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 CHROME_BROWSER_PRINTING_PRINT_PREVIEW_MESSAGE_HANDLER_H_
 #define CHROME_BROWSER_PRINTING_PRINT_PREVIEW_MESSAGE_HANDLER_H_
 
 #include "base/compiler_specific.h"
 #include "base/macros.h"
 #include "content/public/browser/web_contents_observer.h"
 #include "content/public/browser/web_contents_user_data.h"
+#include "printing/features/features.h"
 
 class PrintPreviewUI;
 struct PrintHostMsg_DidGetPreviewPageCount_Params;
 struct PrintHostMsg_DidPreviewDocument_Params;
 struct PrintHostMsg_DidPreviewPage_Params;
 struct PrintHostMsg_RequestPrintPreview_Params;
 struct PrintHostMsg_SetOptionsFromDocument_Params;
 
 namespace content {
 class RenderFrameHost;
 class WebContents;
 }
 
 namespace gfx {
 class Rect;
 }
 
 namespace printing {
 
 struct PageSizeMargins;
 
 // Manages the print preview handling for a WebContents.
 class PrintPreviewMessageHandler
     : public content::WebContentsObserver,
       public content::WebContentsUserData<PrintPreviewMessageHandler> {
  public:
   ~PrintPreviewMessageHandler() override;
 
   // content::WebContentsObserver implementation.
+#if BUILDFLAG(ENABLE_PRINT_BROWSER)
+  void DidFinishLoad(content::RenderFrameHost* render_frame_host,
+                     const GURL& validated_url) override;
+#endif
+
+  // content::WebContentsObserver implementation.
   bool OnMessageReceived(const IPC::Message& message,
                          content::RenderFrameHost* render_frame_host) override;
 
  private:
   explicit PrintPreviewMessageHandler(content::WebContents* web_contents);
   friend class content::WebContentsUserData<PrintPreviewMessageHandler>;
 
   // Gets the print preview dialog associated with the WebContents being
   // observed.
   content::WebContents* GetPrintPreviewDialog();
@@ skipping 18 matching lines @@
   void OnInvalidPrinterSettings(int document_cookie);
   void OnSetOptionsFromDocument(
       const PrintHostMsg_SetOptionsFromDocument_Params& params);
 
   DISALLOW_COPY_AND_ASSIGN(PrintPreviewMessageHandler);
 };
 
 }  // namespace printing
 
 #endif  // CHROME_BROWSER_PRINTING_PRINT_PREVIEW_MESSAGE_HANDLER_H_