[ios] RootCoordinator and view controller.

ios/chrome/browser/root_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.
-
-#import "ios/chrome/browser/root_coordinator.h"
-
-#include "base/logging.h"
-
-#if !defined(__has_feature) || !__has_feature(objc_arc)
-#error "This file requires ARC support."
-#endif
-
-@implementation RootCoordinator
-@synthesize window = _window;
-
-- (instancetype)initWithWindow:(UIWindow*)window {
-  if ((self = [super initWithBaseViewController:nil])) {
-    _window = window;
-  }
-  return self;
-}
-
-- (instancetype)initWithBaseViewController:(UIViewController*)viewController {
-  NOTREACHED();
-  return nil;
-}
-
-@end