Update print preview test to not use CallJavascriptFunctionUnsafe

chrome/browser/ui/webui/print_preview/print_preview_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_UI_WEBUI_PRINT_PREVIEW_PRINT_PREVIEW_HANDLER_H_
 #define CHROME_BROWSER_UI_WEBUI_PRINT_PREVIEW_PRINT_PREVIEW_HANDLER_H_
 
 #include <memory>
 #include <queue>
 #include <string>
@@ skipping 98 matching lines @@
       int http_code) override;
 #endif
 
   int regenerate_preview_request_count() const {
     return regenerate_preview_request_count_;
   }
 
   // Sets |pdf_file_saved_closure_| to |closure|.
   void SetPdfSavedClosureForTesting(const base::Closure& closure);
 
+  // Fires the 'enable-manipulate-settings-for-test' WebUI event.
+  void SendEnableManipulateSettingsForTest();
+
+  // Fires the 'manipulate-settings-for-test' WebUI event with |settings|.
+  void SendManipulateSettingsForTest(const base::DictionaryValue& settings);
+
  protected:
   // If |prompt_user| is true, starts a task to create the default Save As PDF
   // directory if needed. OnDirectoryCreated() will be called when it
   // finishes to open the modal dialog and prompt the user. Otherwise, just
   // accept |default_path| and uniquify it.
   // Protected so unit tests can access.
   virtual void SelectFile(const base::FilePath& default_path, bool prompt_user);
 
   // Handles printing to PDF. Protected to expose to unit tests.
   void PrintToPdf();
@@ skipping 322 matching lines @@
   // Proxy for calls to the print backend.  Lazily initialized since web_ui() is
   // not available at construction time.
   std::unique_ptr<printing::PrinterBackendProxy> printer_backend_proxy_;
 
   base::WeakPtrFactory<PrintPreviewHandler> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(PrintPreviewHandler);
 };
 
 #endif  // CHROME_BROWSER_UI_WEBUI_PRINT_PREVIEW_PRINT_PREVIEW_HANDLER_H_