Standardize usage of virtual/override/final specifiers.

content/browser/battery_status/battery_status_browsertest.cc

Index: content/browser/battery_status/battery_status_browsertest.cc
diff --git a/content/browser/battery_status/battery_status_browsertest.cc b/content/browser/battery_status/battery_status_browsertest.cc
index 70d5a588f84c6bbbe80abe334fbf485376ac0acb..7da7f86d082d0b238390d04db3a07c70fb2235f1 100644
--- a/content/browser/battery_status/battery_status_browsertest.cc
+++ b/content/browser/battery_status/battery_status_browsertest.cc
@@ -89,7 +89,7 @@ class BatteryStatusBrowserTest : public ContentBrowserTest  {
         battery_manager.Pass());
   }
 
-  virtual void TearDown() override {
+  void TearDown() override {
     battery_service_->SetBatteryManagerForTesting(
         scoped_ptr<device::BatteryStatusManager>());
     battery_manager_ = NULL;