Modernize to C++11: use override.

atom/renderer/api/atom_api_web_frame.cc

@@ -39,7 +39,7 @@ class ScriptExecutionCallback : public blink::WebScriptExecutionCallback {
 
   explicit ScriptExecutionCallback(const CompletionCallback& callback)
       : callback_(callback) {}
-  ~ScriptExecutionCallback() {}
+  ~ScriptExecutionCallback() override {}
 
   void completed(
       const blink::WebVector<v8::Local<v8::Value>>& result) override {

chromium_src/chrome/browser/printing/print_job_worker.cc

@@ -38,10 +38,10 @@ void HoldRefCallback(const scoped_refptr<printing::PrintJobWorkerOwner>& owner,
 class PrintingContextDelegate : public PrintingContext::Delegate {
  public:
   PrintingContextDelegate(int render_process_id, int render_view_id);
-  virtual ~PrintingContextDelegate();
+  ~PrintingContextDelegate() override;
 
-  virtual gfx::NativeView GetParentView() override;
-  virtual std::string GetAppLocale() override;
+  gfx::NativeView GetParentView() override;
+  std::string GetAppLocale() override;
 
  private:
   int render_process_id_;