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

ppapi/proxy/isolated_file_system_private_resource.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.
 //
 // CRX filesystem is a filesystem that allows an extension to read its own
 // package directory tree.  See ppapi/examples/crxfs for example.
 //
 // IMPLEMENTATION
 //
 // The implementation involves both browser and renderer.  In order to provide
@@ skipping 23 matching lines @@
 namespace proxy {
 
 class ResourceMessageReplyParams;
 
 class PPAPI_PROXY_EXPORT IsolatedFileSystemPrivateResource
     : public PluginResource,
       public thunk::PPB_IsolatedFileSystem_Private_API {
  public:
   IsolatedFileSystemPrivateResource(
       Connection connection, PP_Instance instance);
-  virtual ~IsolatedFileSystemPrivateResource();
+  ~IsolatedFileSystemPrivateResource() override;
 
   // Resource overrides.
-  virtual thunk::PPB_IsolatedFileSystem_Private_API*
+  thunk::PPB_IsolatedFileSystem_Private_API*
       AsPPB_IsolatedFileSystem_Private_API() override;
 
   // PPB_IsolatedFileSystem_Private_API implementation.
-  virtual int32_t Open(PP_Instance instance,
-                       PP_IsolatedFileSystemType_Private type,
-                       PP_Resource* file_system_resource,
-                       scoped_refptr<TrackedCallback> callback) override;
+  int32_t Open(PP_Instance instance,
+               PP_IsolatedFileSystemType_Private type,
+               PP_Resource* file_system_resource,
+               scoped_refptr<TrackedCallback> callback) override;
 
  private:
   void OnBrowserOpenComplete(PP_IsolatedFileSystemType_Private type,
                              PP_Resource* file_system_resource,
                              scoped_refptr<TrackedCallback> callback,
                              const ResourceMessageReplyParams& params,
                              const std::string& fsid);
 
   DISALLOW_COPY_AND_ASSIGN(IsolatedFileSystemPrivateResource);
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_ISOLATED_FILE_SYSTEM_PRIVATE_RESOURCE_H_