[iOS Clean] Added dialogs UI support.

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

+// 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_coordinator.h"
+
+#include "base/logging.h"
+#import "ios/clean/chrome/browser/ui/dialogs/dialog_coordinator+subclassing.h"
+#import "ios/clean/chrome/browser/ui/dialogs/dialog_mediator.h"
+#import "ios/clean/chrome/browser/ui/dialogs/dialog_view_controller.h"
+#import "ios/clean/chrome/browser/ui/overlay_service/browser_coordinator+overlay_support.h"
+#import "ios/shared/chrome/browser/ui/browser_list/browser.h"
+#import "ios/shared/chrome/browser/ui/commands/command_dispatcher.h"
+
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+@interface DialogCoordinator () {
+  // Backing variable for property of same name (from OverlaySupport category).
+  OverlayQueue* _overlayQueue;
+}
+
+// The dispatcher for DialogDismissalCommands.
+@property(nonatomic, readonly) id<DialogDismissalCommands> dismissalDispatcher;
+// The view controller used to display this dialog.
+@property(nonatomic, strong) DialogViewController* viewController;
+
+@end
+
+@implementation DialogCoordinator
+@synthesize viewController = _viewController;
+
+#pragma mark - Accessors
+
+- (id<DialogDismissalCommands>)dismissalDispatcher {
+  return static_cast<id<DialogDismissalCommands>>(self.browser->dispatcher());
+}
+
+#pragma mark - BrowserCoordinator
+
+- (void)start {
+  DCHECK(self.overlayQueue);
+  DCHECK(self.mediator);
+  self.viewController =
+      [[DialogViewController alloc] initWithStyle:self.alertStyle
+                                       dispatcher:self.dismissalDispatcher];
+  [self.mediator updateConsumer:self.viewController];
+  [self.browser->dispatcher()
+      startDispatchingToTarget:self.mediator
+                   forProtocol:@protocol(DialogDismissalCommands)];
+  [super start];
+}
+
+- (void)stop {
+  [self.browser->dispatcher() stopDispatchingToTarget:self.mediator];
+  [super stop];
+  [self overlayWasStopped];
+}
+
+@end
+
+@implementation DialogCoordinator (OverlaySupport)
+
+- (BOOL)supportsOverlaying {
+  return YES;
+}
+
+- (void)setOverlayQueue:(OverlayQueue*)overlayQueue {
+  _overlayQueue = overlayQueue;
+}
+
+- (OverlayQueue*)overlayQueue {
+  return _overlayQueue;
+}
+
+@end
+
+@implementation DialogCoordinator (Subclassing)
+
+- (UIAlertControllerStyle)alertStyle {
+  return UIAlertControllerStyleAlert;
+}
+
+- (DialogMediator*)mediator {
+  // Subclasses implement.
+  return nil;
+}
+
+@end