Update virtual/final usage in url/.

url/url_canon_stdstring.h

Index: url/url_canon_stdstring.h
diff --git a/url/url_canon_stdstring.h b/url/url_canon_stdstring.h
index 62622b4b7e2e1b2012cdcddcf50c2f22a37152c7..c3d8ba141cc45ef4bfb3bbfde9d67256389050ca 100644
--- a/url/url_canon_stdstring.h
+++ b/url/url_canon_stdstring.h
@@ -36,12 +36,12 @@ namespace url {
 class URL_EXPORT StdStringCanonOutput : public CanonOutput {
  public:
   StdStringCanonOutput(std::string* str);
-  virtual ~StdStringCanonOutput();
+  ~StdStringCanonOutput() override;
 
   // Must be called after writing has completed but before the string is used.
   void Complete();
 
-  virtual void Resize(int sz) override;
+  void Resize(int sz) override;
 
  protected:
   std::string* str_;