[iOS Clean] Added dialogs UI support.

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

Index: ios/clean/chrome/browser/ui/dialogs/dialog_mediator.mm
diff --git a/ios/clean/chrome/browser/ui/dialogs/dialog_mediator.mm b/ios/clean/chrome/browser/ui/dialogs/dialog_mediator.mm
new file mode 100644
index 0000000000000000000000000000000000000000..fcbb10f6b780bbfc35246ee2c577e32de68fc958
--- /dev/null
+++ b/ios/clean/chrome/browser/ui/dialogs/dialog_mediator.mm
@@ -0,0 +1,60 @@
+// 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.
+
+#import "ios/clean/chrome/browser/ui/dialogs/dialog_mediator.h"
+
+#include "base/logging.h"
+#import "ios/clean/chrome/browser/ui/commands/dialog_commands.h"
+#import "ios/clean/chrome/browser/ui/dialogs/dialog_button_configuration.h"
+#import "ios/clean/chrome/browser/ui/dialogs/dialog_consumer.h"
+#import "ios/clean/chrome/browser/ui/dialogs/dialog_mediator+subclassing.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+@implementation DialogMediator
+
+#pragma mark - Public
+
+- (void)updateConsumer:(id<DialogConsumer>)consumer {
+  [consumer setDialogTitle:[self dialogTitle]];
+  [consumer setDialogMessage:[self dialogMessage]];
+  [consumer setDialogButtonConfigurations:[self buttonConfigs]];
+  [consumer setDialogTextFieldConfigurations:[self textFieldConfigs]];
+}
+
+#pragma mark - DialogDismissalCommands
+
+- (void)dismissDialogWithButtonID:(id)buttonID
+                  textFieldValues:
+                      (NSDictionary<id, NSString*>*)textFieldValues {
+  // Implemented by subclasses.
+}
+
+@end
+
+@implementation DialogMediator (Subclassing)
+
+- (NSString*)dialogTitle {
+  // Implemented by subclasses.
+  return nil;
+}
+
+- (NSString*)dialogMessage {
+  // Implemented by subclasses.
+  return nil;
+}
+
+- (NSArray<DialogButtonConfiguration*>*)buttonConfigs {
+  // Implemented by subclasses.
+  return nil;
+}
+
+- (NSArray<DialogTextFieldConfiguration*>*)textFieldConfigs {
+  // Implemented by subclasses.
+  return nil;
+}
+
+@end