replace 'virtual ... OVERRIDE' with '... override'

base/synchronization/waitable_event_posix.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <algorithm>
 #include <vector>
 
 #include "base/logging.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/synchronization/condition_variable.h"
@@ skipping 73 matching lines @@
 // -----------------------------------------------------------------------------
 class SyncWaiter : public WaitableEvent::Waiter {
  public:
   SyncWaiter()
       : fired_(false),
         signaling_event_(NULL),
         lock_(),
         cv_(&lock_) {
   }
 
-  virtual bool Fire(WaitableEvent* signaling_event) OVERRIDE {
+  bool Fire(WaitableEvent* signaling_event) override {
     base::AutoLock locked(lock_);
 
     if (fired_)
       return false;
 
     fired_ = true;
     signaling_event_ = signaling_event;
 
     cv_.Broadcast();
 
     // Unlike AsyncWaiter objects, SyncWaiter objects are stack-allocated on
     // the blocking thread's stack.  There is no |delete this;| in Fire.  The
     // SyncWaiter object is destroyed when it goes out of scope.
 
     return true;
   }
 
   WaitableEvent* signaling_event() const {
     return signaling_event_;
   }
 
   // ---------------------------------------------------------------------------
   // These waiters are always stack allocated and don't delete themselves. Thus
   // there's no problem and the ABA tag is the same as the object pointer.
   // ---------------------------------------------------------------------------
-  virtual bool Compare(void* tag) OVERRIDE {
-    return this == tag;
-  }
+  bool Compare(void* tag) override { return this == tag; }
 
   // ---------------------------------------------------------------------------
   // Called with lock held.
   // ---------------------------------------------------------------------------
   bool fired() const {
     return fired_;
   }
 
   // ---------------------------------------------------------------------------
   // During a TimedWait, we need a way to make sure that an auto-reset
@@ skipping 275 matching lines @@
       return true;
     }
   }
 
   return false;
 }
 
 // -----------------------------------------------------------------------------
 
 }  // namespace base