[iOS Clean] Added dialogs UI support.

ios/clean/chrome/browser/ui/dialogs/dialog_mediator.h

Index: ios/clean/chrome/browser/ui/dialogs/dialog_mediator.h
diff --git a/ios/clean/chrome/browser/ui/dialogs/dialog_mediator.h b/ios/clean/chrome/browser/ui/dialogs/dialog_mediator.h
new file mode 100644
index 0000000000000000000000000000000000000000..9eb254215b73b77f049d6eafbba33eea9817b1a5
--- /dev/null
+++ b/ios/clean/chrome/browser/ui/dialogs/dialog_mediator.h
@@ -0,0 +1,24 @@
+// 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_DIALOG_MEDIATOR_H_
+#define IOS_CLEAN_CHROME_BROWSER_UI_DIALOGS_DIALOG_MEDIATOR_H_
+
+#import <Foundation/Foundation.h>
+
+#import "ios/clean/chrome/browser/ui/commands/dialog_commands.h"
+
+@protocol DialogConsumer;
+
+// Class responsible for setting up a DialogConsumer.  This class is meant to be
+// subclassed, and subclasses are expected to implement the interface in the
+// DialogMediator+Subclassing category.
+@interface DialogMediator : NSObject<DialogDismissalCommands>
+
+// Supplies UI information to |consumer|.
+- (void)updateConsumer:(id<DialogConsumer>)consumer;
+
+@end
+
+#endif  // IOS_CLEAN_CHROME_BROWSER_UI_DIALOGS_DIALOG_MEDIATOR_H_