[iOS Clean] Added HTTP authentication dialog support.

ios/clean/chrome/browser/ui/dialogs/http_auth_dialogs/http_auth_dialog_mediator.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 IOS_CLEAN_CHROME_BROWSER_UI_DIALOGS_HTTP_AUTH_DIALOGS_HTTP_AUTH_DIALOG_MEDIATOR_H_
+#define IOS_CLEAN_CHROME_BROWSER_UI_DIALOGS_HTTP_AUTH_DIALOGS_HTTP_AUTH_DIALOG_MEDIATOR_H_
+
+#import "ios/clean/chrome/browser/ui/dialogs/dialog_mediator.h"
+
+@protocol HTTPAuthDialogDismissalCommands;
+@class HTTPAuthDialogRequest;
+
+// Class responsible for setting up a DialogConsumer for HTTP auth dialogs.
+@interface HTTPAuthDialogMediator : DialogMediator
+
+// Designated initializer for a mediator that uses |request| to provide datat to
+// consumers, and |dispatcher| to communicate HTTP auth dismissal commands.
+// Both are expected to be non-nil.
+- (instancetype)initWithRequest:(HTTPAuthDialogRequest*)request
+                     dispatcher:(id<HTTPAuthDialogDismissalCommands>)dispatcher
+    NS_DESIGNATED_INITIALIZER;
+- (instancetype)init NS_UNAVAILABLE;
+
+@end
+
+#endif  // IOS_CLEAN_CHROME_BROWSER_UI_DIALOGS_HTTP_AUTH_DIALOGS_HTTP_AUTH_DIALOG_MEDIATOR_H_