Remove unnecessary 'virtual' annotation from mojo

mojo/services/html_viewer/webthemeengine_impl.h

Index: mojo/services/html_viewer/webthemeengine_impl.h
diff --git a/mojo/services/html_viewer/webthemeengine_impl.h b/mojo/services/html_viewer/webthemeengine_impl.h
index ed59d1a772129fe578bfaa919b740515dbebf59f..6b0dad145c6581be635907f0c519d977bf1f957f 100644
--- a/mojo/services/html_viewer/webthemeengine_impl.h
+++ b/mojo/services/html_viewer/webthemeengine_impl.h
@@ -12,13 +12,12 @@ namespace html_viewer {
 class WebThemeEngineImpl : public blink::WebThemeEngine {
  public:
   // WebThemeEngine methods:
-  virtual blink::WebSize getSize(blink::WebThemeEngine::Part);
-  virtual void paint(
-      blink::WebCanvas* canvas,
-      blink::WebThemeEngine::Part part,
-      blink::WebThemeEngine::State state,
-      const blink::WebRect& rect,
-      const blink::WebThemeEngine::ExtraParams* extra_params);
+  blink::WebSize getSize(blink::WebThemeEngine::Part) override;
+  void paint(blink::WebCanvas* canvas,
+             blink::WebThemeEngine::Part part,
+             blink::WebThemeEngine::State state,
+             const blink::WebRect& rect,
+             const blink::WebThemeEngine::ExtraParams* extra_params) override;
   virtual void paintStateTransition(blink::WebCanvas* canvas,
                                     blink::WebThemeEngine::Part part,
                                     blink::WebThemeEngine::State startState,