[Clean Skeleton] Migrate code to clean/

ios/chrome/browser/ui/web_contents/web_coordinator.mm

-// Copyright 2016 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.
-
-// ======                        New Architecture                         =====
-// =         This code is only used in the new iOS Chrome architecture.       =
-// ============================================================================
-
-#import "ios/chrome/browser/ui/web_contents/web_coordinator.h"
-
-#import "ios/chrome/browser/browser_coordinator+internal.h"
-#import "ios/chrome/browser/ui/web_contents/web_contents_view_controller.h"
-
-#if !defined(__has_feature) || !__has_feature(objc_arc)
-#error "This file requires ARC support."
-#endif
-
-@interface WebCoordinator ()
-
-@property(nonatomic, strong) WebContentsViewController* viewController;
-@property(nonatomic, readwrite, strong) WebMediator* webMediator;
-
-@end
-
-@implementation WebCoordinator
-@synthesize webMediator = _webMediator;
-@synthesize viewController = _viewController;
-
-- (void)start {
-  self.viewController = [[WebContentsViewController alloc]
-      initWithWebState:self.webMediator.webState];
-
-  // Reminder: this is a no-op if |rootViewController| is nil, for example
-  // when this coordinator's view controller will be contained instead of
-  // presented.
-  [self.rootViewController presentViewController:self.viewController
-                                        animated:YES
-                                      completion:nil];
-}
-
-- (void)setWebState:(web::WebState*)webState {
-  self.webMediator = [[WebMediator alloc] initWithWebState:webState];
-}
-
-@end