Replace MessagePumpForUI with MessagePumpDefault in unit tests.

base/test/test_support_ios.mm

+// 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 "base/message_loop.h"
+#include "base/message_pump_default.h"
+
+namespace {
+
+base::MessagePump* CreateMessagePumpForUIForTests() {
+  // A default MessagePump will do quite nicely in tests.
+  return new base::MessagePumpDefault();
+}
+
+}  // namespace
+
+namespace base {
+
+void InitIOSTestMessageLoop() {
+  MessageLoop::InitMessagePumpForUIFactory(&CreateMessagePumpForUIForTests);
+}
+
+}  // namespace base