Add WidgetViewController

Not yet use

Riot/ViewController/Widgets/WidgetViewController.h

@@ -0,0 +1,33 @@
+/*
+ Copyright 2017 Vector Creations Ltd
+
+ Licensed under the Apache License, Version 2.0 (the "License");
+ you may not use this file except in compliance with the License.
+ You may obtain a copy of the License at
+
+ http://www.apache.org/licenses/LICENSE-2.0
+
+ Unless required by applicable law or agreed to in writing, software
+ distributed under the License is distributed on an "AS IS" BASIS,
+ WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ See the License for the specific language governing permissions and
+ limitations under the License.
+ */
+
+#import "WebViewViewController.h"
+
+#import "WidgetManager.h"
+
+/**
+ `WidgetViewController` displays widget within a webview.
+ */
+@interface WidgetViewController : WebViewViewController
+
+/**
+ Init 'WidgetViewController' instance with a widget.
+
+ @param widget the widget to open.
+ */
+- (instancetype)initForWidget:(Widget*)widget;
+
+@end