Upstream Chrome on iOS source code [6/11].

ios/chrome/browser/ui/page_not_available_controller.h

+// Copyright 2012 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 IOS_CHROME_BROWSER_UI_PAGE_NOT_AVAILABLE_CONTROLLER_H_
+#define IOS_CHROME_BROWSER_UI_PAGE_NOT_AVAILABLE_CONTROLLER_H_
+
+#import "ios/chrome/browser/ui/native_content_controller.h"
+
+// A native controller for the case where the URL is not valid and/or the page
+// is not available.
+@interface PageNotAvailableController : NativeContentController
+
+// Property to allow setting a custom description for the content.
+@property(nonatomic, assign) NSString* descriptionText;
+
+// Designated initializer.
+- (instancetype)initWithUrl:(const GURL&)url NS_DESIGNATED_INITIALIZER;
+
+- (instancetype)initWithNibName:(NSString*)nibName
+                            url:(const GURL&)url NS_UNAVAILABLE;
+
+@end
+
+#endif  // IOS_CHROME_BROWSER_UI_PAGE_NOT_AVAILABLE_CONTROLLER_H_