[CRD iOS] Branching internal and external implementations

remoting/ios/app/panel_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_PANEL_VIEW_CONTROLLER_H_
+#define REMOTING_IOS_APP_PANEL_VIEW_CONTROLLER_H_
+
+#import <UIKit/UIKit.h>
+
+// Interface for a view controller to open the side menu on top of the main view
+// controller. Implementation should be subclass of UIViewController.
+@protocol PanelViewController<NSObject>
+
+- (void)setPanelHidden:(BOOL)hidden animated:(BOOL)animated;
+
+@property(nonatomic) UIViewController* mainViewController;
+
+@end
+
+@interface PanelViewControllerFactory : NSObject
+
++ (UIViewController<PanelViewController>*)createController;
+
+@property(class, nonatomic) Class controllerClass;
+
+@end
+
+#endif  // REMOTING_IOS_APP_PANEL_VIEW_CONTROLLER_H_