Update from https://crrev.com/306655

base/synchronization/waitable_event.h

Index: base/synchronization/waitable_event.h
diff --git a/base/synchronization/waitable_event.h b/base/synchronization/waitable_event.h
index 39c0d11538cdf68727893eb0fd1beea91a83b8d0..5adc1ec64034aaa1370caa98c41d85e475010af8 100644
--- a/base/synchronization/waitable_event.h
+++ b/base/synchronization/waitable_event.h
@@ -53,11 +53,7 @@ class BASE_EXPORT WaitableEvent {
   // Create a WaitableEvent from an Event HANDLE which has already been
   // created. This objects takes ownership of the HANDLE and will close it when
   // deleted.
-  // TODO(rvargas): Pass ScopedHandle instead (and on Release).
-  explicit WaitableEvent(HANDLE event_handle);
-
-  // Releases ownership of the handle from this object.
-  HANDLE Release();
+  explicit WaitableEvent(win::ScopedHandle event_handle);
 #endif
 
   ~WaitableEvent();