libchromeos: Migrate AsyncEventSequencer to libchromeos

This enables sharing this functionality between peerd and buffet.

BUG=chromium:398626
TEST=libchromeos/buffet unittests

Change-Id: Ic38b9bbf491b57d18b0409f0587efedeab6ef988
Reviewed-on: https://chromium-review.googlesource.com/210402
Reviewed-by: Alex Vakulenko <avakulenko@chromium.org>
Commit-Queue: Alex Vakulenko <avakulenko@chromium.org>
Tested-by: Alex Vakulenko <avakulenko@chromium.org>
diff --git a/buffet/main.cc b/buffet/main.cc
index 358358e..eb25d13 100644
--- a/buffet/main.cc
+++ b/buffet/main.cc
@@ -12,15 +12,15 @@
 #include <base/message_loop/message_loop.h>
 #include <base/strings/string_util.h>
 #include <base/strings/stringprintf.h>
+#include <chromeos/async_event_sequencer.h>
 #include <dbus/bus.h>
 #include <sysexits.h>
 
-#include "buffet/async_event_sequencer.h"
 #include "buffet/dbus_constants.h"
 #include "buffet/exported_object_manager.h"
 #include "buffet/manager.h"
 
-using buffet::dbus_utils::AsyncEventSequencer;
+using chromeos::dbus_utils::AsyncEventSequencer;
 using buffet::dbus_utils::ExportedObjectManager;
 
 namespace {