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

ppapi/proxy/host_resolver_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.
 
 #ifndef PPAPI_PROXY_HOST_RESOLVER_RESOURCE_H_
 #define PPAPI_PROXY_HOST_RESOLVER_RESOURCE_H_
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "ppapi/proxy/host_resolver_resource_base.h"
 #include "ppapi/proxy/ppapi_proxy_export.h"
 #include "ppapi/thunk/ppb_host_resolver_api.h"
 
 namespace ppapi {
 namespace proxy {
 
 class PPAPI_PROXY_EXPORT HostResolverResource
     : public HostResolverResourceBase,
       public thunk::PPB_HostResolver_API {
  public:
   HostResolverResource(Connection connection, PP_Instance instance);
-  virtual ~HostResolverResource();
+  ~HostResolverResource() override;
 
   // PluginResource overrides.
-  virtual thunk::PPB_HostResolver_API* AsPPB_HostResolver_API() override;
+  thunk::PPB_HostResolver_API* AsPPB_HostResolver_API() override;
 
   // thunk::PPB_HostResolver_API implementation.
-  virtual int32_t Resolve(const char* host,
-                          uint16_t port,
-                          const PP_HostResolver_Hint* hint,
-                          scoped_refptr<TrackedCallback> callback) override;
-  virtual PP_Var GetCanonicalName() override;
-  virtual uint32_t GetNetAddressCount() override;
-  virtual PP_Resource GetNetAddress(uint32_t index) override;
+  int32_t Resolve(const char* host,
+                  uint16_t port,
+                  const PP_HostResolver_Hint* hint,
+                  scoped_refptr<TrackedCallback> callback) override;
+  PP_Var GetCanonicalName() override;
+  uint32_t GetNetAddressCount() override;
+  PP_Resource GetNetAddress(uint32_t index) override;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(HostResolverResource);
 };
 
 }  // namespace proxy
 }  // namespace ppapi
 
 #endif  // PPAPI_PROXY_HOST_RESOLVER_RESOURCE_H_