Mojo: Convert the remaining OVERRIDEs to override in mojo/.

mojo/services/html_viewer/webthread_impl.cc

Index: mojo/services/html_viewer/webthread_impl.cc
diff --git a/mojo/services/html_viewer/webthread_impl.cc b/mojo/services/html_viewer/webthread_impl.cc
index ae108e416d78ff01cd375ca8b6e5cbd4f58ce8f2..678d22e77f8ce0d8899344476abf9db800fd9685 100644
--- a/mojo/services/html_viewer/webthread_impl.cc
+++ b/mojo/services/html_viewer/webthread_impl.cc
@@ -24,11 +24,11 @@ class WebThreadBase::TaskObserverAdapter
   TaskObserverAdapter(WebThread::TaskObserver* observer)
       : observer_(observer) {}
 
-  virtual void WillProcessTask(const base::PendingTask& pending_task) OVERRIDE {
+  virtual void WillProcessTask(const base::PendingTask& pending_task) override {
     observer_->willProcessTask();
   }
 
-  virtual void DidProcessTask(const base::PendingTask& pending_task) OVERRIDE {
+  virtual void DidProcessTask(const base::PendingTask& pending_task) override {
     observer_->didProcessTask();
   }