Add the "virtual" keyword on method overrides that are missing it.

chrome/browser/policy/file_based_policy_provider.h

 // Copyright (c) 2010 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_POLICY_FILE_BASED_POLICY_PROVIDER_H_
 #define CHROME_BROWSER_POLICY_FILE_BASED_POLICY_PROVIDER_H_
 #pragma once
 
 #include "base/basictypes.h"
 #include "base/file_path.h"
@@ skipping 88 matching lines @@
   // called on the file thread.
   void Reload();
 
   // Gets the current dictionary value object. Ownership of the returned value
   // is transferred to the caller.
   DictionaryValue* GetPolicy();
 
   const FilePath& config_file_path() { return delegate_->config_file_path(); }
 
   // FilePathWatcher::Delegate implementation:
-  void OnFilePathChanged(const FilePath& path);
-  void OnError();
+  virtual void OnFilePathChanged(const FilePath& path);
+  virtual void OnError();
 
  private:
   // FileBasedPolicyLoader objects should only be deleted by
   // RefCountedThreadSafe.
   friend class base::RefCountedThreadSafe<FileBasedPolicyLoader>;
   virtual ~FileBasedPolicyLoader();
 
   // Checks whether reading policy information  is safe to do. If not, returns
   // false and the delay until it is considered safe to reload in |delay|.
   bool IsSafeToReloadPolicy(const base::Time& now, base::TimeDelta* delay);
@@ skipping 69 matching lines @@
 
   // Wrapped watcher that takes care of the actual watching.
   FilePathWatcher watcher_;
 
   DISALLOW_COPY_AND_ASSIGN(FileBasedPolicyWatcher);
 };
 
 }  // namespace policy
 
 #endif  // CHROME_BROWSER_POLICY_FILE_BASED_POLICY_PROVIDER_H_