mash: Change CastConfigDelegate to a mojoified CastConfigClient.

ash/common/cast_config_delegate.cc

Index: ash/common/cast_config_delegate.cc
diff --git a/ash/common/cast_config_delegate.cc b/ash/common/cast_config_delegate.cc
deleted file mode 100644
index 53de51a1c0fdfef1522e70258d9a024eecc3768c..0000000000000000000000000000000000000000
--- a/ash/common/cast_config_delegate.cc
+++ /dev/null
@@ -1,21 +0,0 @@
-// 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 "ash/common/cast_config_delegate.h"
-
-namespace ash {
-
-CastConfigDelegate::Sink::Sink() {}
-
-CastConfigDelegate::Sink::~Sink() {}
-
-CastConfigDelegate::Route::Route() {}
-
-CastConfigDelegate::Route::~Route() {}
-
-CastConfigDelegate::SinkAndRoute::SinkAndRoute() {}
-
-CastConfigDelegate::SinkAndRoute::~SinkAndRoute() {}
-
-}  // namespace ash