Sync ui/events to chromium @ https://codereview.chromium.org/1210203002

ui/events/null_event_targeter.cc

+// Copyright 2015 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 "base/logging.h"
+#include "ui/events/null_event_targeter.h"
+
+namespace ui {
+
+NullEventTargeter::NullEventTargeter() {
+}
+
+NullEventTargeter::~NullEventTargeter() {
+}
+
+EventTarget* NullEventTargeter::FindTargetForEvent(EventTarget* root,
+                                                   Event* event) {
+  return nullptr;
+}
+
+EventTarget* NullEventTargeter::FindNextBestTarget(EventTarget* previous_target,
+                                                   Event* event) {
+  NOTREACHED();
+  return nullptr;
+}
+
+}  // namespace ui