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

cloud_print/gcp20/prototype/cloud_print_request.h

Index: cloud_print/gcp20/prototype/cloud_print_request.h
diff --git a/cloud_print/gcp20/prototype/cloud_print_request.h b/cloud_print/gcp20/prototype/cloud_print_request.h
index 681299f582ee625153201e1e244498f8b5d412d6..5cd83577c0cd8a4edc6fff5ac9df18c0066bc3cf 100644
--- a/cloud_print/gcp20/prototype/cloud_print_request.h
+++ b/cloud_print/gcp20/prototype/cloud_print_request.h
@@ -38,7 +38,7 @@ class CloudPrintRequest : public net::URLFetcherDelegate,
     virtual void OnFetchTimeoutReached() = 0;
   };
 
-  virtual ~CloudPrintRequest();
+  ~CloudPrintRequest() override;
 
   // Creates GET request.
   static scoped_ptr<CloudPrintRequest> CreateGet(const GURL& url,
@@ -63,7 +63,7 @@ class CloudPrintRequest : public net::URLFetcherDelegate,
                     Delegate* delegate);
 
   // net::URLFetcherDelegate methods:
-  virtual void OnURLFetchComplete(const net::URLFetcher* source) override;
+  void OnURLFetchComplete(const net::URLFetcher* source) override;
 
   // Method for handling timeout.
   void OnRequestTimeout();