Make WaitableEvent's constructor enum-based.

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 <stddef.h>
 
 #include <algorithm>
 #include <vector>
 
 #include "base/logging.h"
@@ skipping 25 matching lines @@
 
 namespace base {
 
 // -----------------------------------------------------------------------------
 // This is just an abstract base class for waking the two types of waiters
 // -----------------------------------------------------------------------------
 WaitableEvent::WaitableEvent(bool manual_reset, bool initially_signaled)
     : kernel_(new WaitableEventKernel(manual_reset, initially_signaled)) {
 }
 
+WaitableEvent::WaitableEvent(ResetPolicy reset_policy,
+                             InitialState initial_state)
+    : WaitableEvent(reset_policy == ResetPolicy::MANUAL,
+                    initial_state == InitialState::SIGNALED) {}
+
 WaitableEvent::~WaitableEvent() {
 }
 
 void WaitableEvent::Reset() {
   base::AutoLock locked(kernel_->lock_);
   kernel_->signaled_ = false;
 }
 
 void WaitableEvent::Signal() {
   base::AutoLock locked(kernel_->lock_);
@@ skipping 352 matching lines @@
       return true;
     }
   }
 
   return false;
 }
 
 // -----------------------------------------------------------------------------
 
 }  // namespace base