[ObjC ARC] Converts ios/chrome/browser/payments:payments to ARC.

ios/chrome/browser/payments/shipping_option_selection_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/chrome/browser/payments/shipping_option_selection_coordinator.h"
 
-#import "base/ios/weak_nsobject.h"
-#include "base/mac/scoped_nsobject.h"
 #include "base/strings/sys_string_conversions.h"
 #import "ios/chrome/browser/payments/payment_request_util.h"
 
-@interface ShippingOptionSelectionCoordinator () {
-  base::WeakNSProtocol<id<ShippingOptionSelectionCoordinatorDelegate>>
-      _delegate;
-  base::scoped_nsobject<ShippingOptionSelectionViewController> _viewController;
-}
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+@interface ShippingOptionSelectionCoordinator ()
+
+@property(nonatomic, strong)
+    ShippingOptionSelectionViewController* viewController;
 
 // Called when the user selects a shipping option. The cell is checked, the
 // UI is locked so that the user can't interact with it, then the delegate is
 // notified. The delay is here to let the user get a visual feedback of the
 // selection before this view disappears.
 - (void)delayedNotifyDelegateOfSelection:
     (web::PaymentShippingOption*)shippingOption;
 
 @end
 
 @implementation ShippingOptionSelectionCoordinator
 
 @synthesize paymentRequest = _paymentRequest;
-
-- (id<ShippingOptionSelectionCoordinatorDelegate>)delegate {
-  return _delegate.get();
-}
-
-- (void)setDelegate:(id<ShippingOptionSelectionCoordinatorDelegate>)delegate {
-  _delegate.reset(delegate);
-}
+@synthesize delegate = _delegate;
+@synthesize viewController = _viewController;
 
 - (void)start {
-  _viewController.reset([[ShippingOptionSelectionViewController alloc]
-      initWithPaymentRequest:_paymentRequest]);
+  _viewController = [[ShippingOptionSelectionViewController alloc]
+      initWithPaymentRequest:_paymentRequest];
   [_viewController setDelegate:self];
   [_viewController loadModel];
 
   DCHECK(self.baseViewController.navigationController);
   [self.baseViewController.navigationController
       pushViewController:_viewController
                 animated:YES];
 }
 
 - (void)stop {
   [self.baseViewController.navigationController popViewControllerAnimated:YES];
-  _viewController.reset();
+  _viewController = nil;
 }
 
 - (void)stopSpinnerAndDisplayError {
   // Re-enable user interactions that were disabled earlier in
   // delayedNotifyDelegateOfSelection.
-  _viewController.get().view.userInteractionEnabled = YES;
+  _viewController.view.userInteractionEnabled = YES;
 
   [_viewController setIsLoading:NO];
   NSString* errorMessage =
       payment_request_util::GetShippingOptionSelectorErrorMessage(
           _paymentRequest);
   [_viewController setErrorMessage:errorMessage];
   [_viewController loadModel];
   [[_viewController collectionView] reloadData];
 }
 
 #pragma mark - ShippingOptionSelectionViewControllerDelegate
 
 - (void)shippingOptionSelectionViewController:
             (ShippingOptionSelectionViewController*)controller
                       didSelectShippingOption:
                           (web::PaymentShippingOption*)shippingOption {
   [self delayedNotifyDelegateOfSelection:shippingOption];
 }
 
 - (void)shippingOptionSelectionViewControllerDidReturn:
     (ShippingOptionSelectionViewController*)controller {
   [_delegate shippingOptionSelectionCoordinatorDidReturn:self];
 }
 
 - (void)delayedNotifyDelegateOfSelection:
     (web::PaymentShippingOption*)shippingOption {
-  _viewController.get().view.userInteractionEnabled = NO;
-  base::WeakNSObject<ShippingOptionSelectionCoordinator> weakSelf(self);
-  dispatch_after(
-      dispatch_time(DISPATCH_TIME_NOW,
-                    static_cast<int64_t>(0.2 * NSEC_PER_SEC)),
-      dispatch_get_main_queue(), ^{
-        base::scoped_nsobject<ShippingOptionSelectionCoordinator> strongSelf(
-            [weakSelf retain]);
-        // Early return if the coordinator has been deallocated.
-        if (!strongSelf)
-          return;
-        [_viewController setIsLoading:YES];
-        [_viewController loadModel];
-        [[_viewController collectionView] reloadData];
+  _viewController.view.userInteractionEnabled = NO;
+  __weak ShippingOptionSelectionCoordinator* weakSelf = self;
+  dispatch_after(dispatch_time(DISPATCH_TIME_NOW,
+                               static_cast<int64_t>(0.2 * NSEC_PER_SEC)),
+                 dispatch_get_main_queue(), ^{
+                   ShippingOptionSelectionCoordinator* strongSelf = weakSelf;
+                   [strongSelf.viewController setIsLoading:YES];
+                   [strongSelf.viewController loadModel];
+                   [[strongSelf.viewController collectionView] reloadData];
 
-        [_delegate shippingOptionSelectionCoordinator:self
-                              didSelectShippingOption:shippingOption];
-      });
+                   [strongSelf.delegate
+                       shippingOptionSelectionCoordinator:strongSelf
+                                  didSelectShippingOption:shippingOption];
+                 });
 }
 
 @end