Update {virtual,override,final} to follow C++11 style in base.

base/android/trace_event_binding.cc

Index: base/android/trace_event_binding.cc
diff --git a/base/android/trace_event_binding.cc b/base/android/trace_event_binding.cc
index 94eb2140325d29a41a207551b37a1e78d56d2ade..b8ce6d9858d6e69b029b91e2ba953f8d4b6ab0db 100644
--- a/base/android/trace_event_binding.cc
+++ b/base/android/trace_event_binding.cc
@@ -57,11 +57,11 @@ class TraceEventDataConverter {
 
 class TraceEnabledObserver : public debug::TraceLog::EnabledStateObserver {
   public:
-    virtual void OnTraceLogEnabled() override {
+   void OnTraceLogEnabled() override {
       JNIEnv* env = base::android::AttachCurrentThread();
       base::android::Java_TraceEvent_setEnabled(env, true);
     }
-    virtual void OnTraceLogDisabled() override {
+    void OnTraceLogDisabled() override {
       JNIEnv* env = base::android::AttachCurrentThread();
       base::android::Java_TraceEvent_setEnabled(env, false);
     }