Standardize usage of virtual/override/final in content/

content/public/test/content_browser_test_utils.cc

Index: content/public/test/content_browser_test_utils.cc
diff --git a/content/public/test/content_browser_test_utils.cc b/content/public/test/content_browser_test_utils.cc
index 47865445eddec02897dec4e0508fb70208f709d4..ba391947fc958ae28085c284815c155fdc8100f4 100644
--- a/content/public/test/content_browser_test_utils.cc
+++ b/content/public/test/content_browser_test_utils.cc
@@ -110,7 +110,7 @@ class RenderViewCreatedObserver : public WebContentsObserver {
   }
 
   // WebContentsObserver:
-  virtual void RenderViewCreated(RenderViewHost* rvh) override {
+  void RenderViewCreated(RenderViewHost* rvh) override {
     render_view_created_called_ = true;
   }