Update {virtual,override} to follow C++11 style in chrome.

chrome/browser/ui/pdf/pdf_browsertest_base.h

 // Copyright 2014 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_PDF_PDF_BROWSERTEST_BASE_H_
 #define CHROME_BROWSER_UI_PDF_PDF_BROWSERTEST_BASE_H_
 
 #include <string>
 
 #include "base/files/file_path.h"
 #include "chrome/test/base/in_process_browser_test.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/readback_types.h"
 #include "net/test/embedded_test_server/embedded_test_server.h"
 
 namespace base {
 class CommandLine;
 }
 
 class SkBitmap;
 
 // This class is in its own separate file because it is used in both
 // browser_tests and interactive_ui_tests.
 class PDFBrowserTest : public InProcessBrowserTest,
                        public testing::WithParamInterface<int>,
                        public content::NotificationObserver {
  public:
   PDFBrowserTest();
-  virtual ~PDFBrowserTest();
+  ~PDFBrowserTest() override;
 
  protected:
   // Use our own TestServer so that we can serve files from the pdf directory.
   net::test_server::EmbeddedTestServer* pdf_test_server() {
     return &pdf_test_server_;
   }
 
   int load_stop_notification_count() const {
     return load_stop_notification_count_;
   }
 
   void Load();
   void WaitForResponse();
   bool VerifySnapshot(const std::string& expected_filename);
 
  private:
   void CopyFromBackingStoreCallback(const SkBitmap& bitmap,
                                     content::ReadbackResponse response);
 
   // content::NotificationObserver
-  virtual void Observe(int type,
-                       const content::NotificationSource& source,
-                       const content::NotificationDetails& details) override;
+  void Observe(int type,
+               const content::NotificationSource& source,
+               const content::NotificationDetails& details) override;
 
   // InProcessBrowserTest
-  virtual void SetUpCommandLine(base::CommandLine* command_line) override;
+  void SetUpCommandLine(base::CommandLine* command_line) override;
 
   // True if the snapshot differed from the expected value.
   bool snapshot_different_;
   // Internal variable used to synchronize to the renderer.
   int next_dummy_search_value_;
   // The filename of the bitmap to compare the snapshot to.
   std::string expected_filename_;
   // If the snapshot is different, holds the location where it's saved.
   base::FilePath snapshot_filename_;
   // How many times we've seen chrome::LOAD_STOP.
   int load_stop_notification_count_;
 
   net::test_server::EmbeddedTestServer pdf_test_server_;
 
   DISALLOW_COPY_AND_ASSIGN(PDFBrowserTest);
 };
 
 #endif  // CHROME_BROWSER_UI_PDF_PDF_BROWSERTEST_BASE_H_