[CRD iOS] Add the host setup instruction page

remoting/ios/app/host_setup_view_controller.h

+// Copyright 2017 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.
+
+#ifndef REMOTING_IOS_APP_HOST_SETUP_VIEW_CONTOLLER_H_
+#define REMOTING_IOS_APP_HOST_SETUP_VIEW_CONTOLLER_H_
+
+#import <UIKit/UIKit.h>
+
+#import "ios/third_party/material_components_ios/src/components/Collections/src/MaterialCollections.h"
+
+// This controller shows instruction for setting up the host a host when the
+// user has no host in the host list.
+@interface HostSetupViewController : MDCCollectionViewController
+
+@property(weak, nonatomic) id<UIScrollViewDelegate> scrollViewDelegate;
+
+@end
+
+#endif  // REMOTING_IOS_APP_HOST_SETUP_VIEW_CONTOLLER_H_