Leave IMasterDetailPageController intact

Xamarin.Forms.Core/FlyoutPage.cs

@@ -315,5 +315,9 @@ public MasterDetailPage()
 		{
 			return _platformConfigurationRegistry.Value.On<T>();
 		}
+
+		[EditorBrowsable(EditorBrowsableState.Never)]
+		public void UpdateMasterBehavior() =>
+			(this as IFlyoutPageController).UpdateFlyoutLayoutBehavior();
 	}
 }

Xamarin.Forms.Core/IFlyoutPageController.cs

@@ -17,8 +17,18 @@ public interface IFlyoutPageController
 		event EventHandler<BackButtonPressedEventArgs> BackButtonPressed;
 	}
 
-	public interface IMasterDetailPageController : IFlyoutPageController
+	public interface IMasterDetailPageController
 	{
+		bool CanChangeIsPresented { get; set; }
+
+		Rectangle DetailBounds { get; set; }
+
 		Rectangle MasterBounds { get; set; }
+
+		bool ShouldShowSplitMode { get; }
+
+		void UpdateMasterBehavior();
+
+		event EventHandler<BackButtonPressedEventArgs> BackButtonPressed;
 	}
 }