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

ios/chrome/browser/ui/settings/time_range_selector_collection_view_controller.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/ui/settings/time_range_selector_collection_view_controller.h"
 
-#import "base/ios/weak_nsobject.h"
 #import "base/mac/foundation_util.h"
-#import "base/mac/scoped_nsobject.h"
 #include "components/browsing_data/core/pref_names.h"
 #include "components/prefs/pref_member.h"
 #include "components/prefs/pref_service.h"
 #import "ios/chrome/browser/ui/collection_view/cells/collection_view_text_item.h"
 #import "ios/chrome/browser/ui/collection_view/collection_view_model.h"
 #include "ios/chrome/grit/ios_strings.h"
 #import "ios/third_party/material_components_ios/src/components/CollectionCells/src/MaterialCollectionCells.h"
 #include "ui/base/l10n/l10n_util_mac.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 
 typedef NS_ENUM(NSInteger, SectionIdentifier) {
   SectionIdentifierOptions = kSectionIdentifierEnumZero,
 };
 
 typedef NS_ENUM(NSInteger, ItemType) {
   ItemTypePastHour = kItemTypeEnumZero,
   ItemTypePastDay,
   ItemTypePastWeek,
@@ skipping 11 matching lines @@
 static_assert(
     arraysize(kStringIDS) ==
         static_cast<int>(browsing_data::TimePeriod::TIME_PERIOD_LAST) + 1,
     "Strings have to match the enum values.");
 
 }  // namespace
 
 @interface TimeRangeSelectorCollectionViewController () {
   // Instance of the parent view controller needed in order to set the time
   // range for the browsing data deletion.
-  base::WeakNSProtocol<id<TimeRangeSelectorCollectionViewControllerDelegate>>
-      _weakDelegate;
+  __weak id<TimeRangeSelectorCollectionViewControllerDelegate> _weakDelegate;
   IntegerPrefMember timeRangePref_;
 }
 
 // Updates the checked state of the cells to match the preferences.
 - (void)updateCheckedState;
 
 // Updates the PrefService with the given value.
 - (void)updatePrefValue:(int)prefValue;
 @end
 
 @implementation TimeRangeSelectorCollectionViewController
 
 #pragma mark Initialization
 
 - (instancetype)
 initWithPrefs:(PrefService*)prefs
      delegate:(id<TimeRangeSelectorCollectionViewControllerDelegate>)delegate {
   self = [super initWithStyle:CollectionViewControllerStyleAppBar];
   if (self) {
-    _weakDelegate.reset(delegate);
+    _weakDelegate = delegate;
     self.title = l10n_util::GetNSString(
         IDS_IOS_CLEAR_BROWSING_DATA_TIME_RANGE_SELECTOR_TITLE);
     timeRangePref_.Init(browsing_data::prefs::kDeleteTimePeriod, prefs);
     [self loadModel];
     self.shouldHideDoneButton = YES;
   }
   return self;
 }
 
 - (void)loadModel {
@@ skipping 48 matching lines @@
 }
 
 - (void)updatePrefValue:(int)prefValue {
   timeRangePref_.SetValue(prefValue);
   [self updateCheckedState];
 }
 
 - (CollectionViewTextItem*)timeRangeItemWithOption:(ItemType)itemOption
                                      textMessageID:(int)textMessageID {
   CollectionViewTextItem* item =
-      [[[CollectionViewTextItem alloc] initWithType:itemOption] autorelease];
+      [[CollectionViewTextItem alloc] initWithType:itemOption];
   [item setText:l10n_util::GetNSString(textMessageID)];
   [item setAccessibilityTraits:UIAccessibilityTraitButton];
   return item;
 }
 
 #pragma mark - UICollectionViewDelegate
 
 - (void)collectionView:(UICollectionView*)collectionView
     didSelectItemAtIndexPath:(NSIndexPath*)indexPath {
   [super collectionView:collectionView didSelectItemAtIndexPath:indexPath];
@@ skipping 14 matching lines @@
 + (NSString*)timePeriodLabelForPrefs:(PrefService*)prefs {
   if (!prefs)
     return nil;
   int prefValue = prefs->GetInteger(browsing_data::prefs::kDeleteTimePeriod);
   if (prefValue < 0 || static_cast<size_t>(prefValue) >= arraysize(kStringIDS))
     return nil;
   return l10n_util::GetNSString(kStringIDS[prefValue]);
 }
 
 @end