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

Automatically generated ARCMigrate commit
Notable issues:None
BUG=624363
TEST=None

Review-Url: https://codereview.chromium.org/2743643002
Cr-Commit-Position: refs/heads/master@{#455785}

ios/chrome/browser/ui/collection_view/BUILD.gn

@@ -3,6 +3,7 @@
 # found in the LICENSE file.
 
 source_set("collection_view") {
+  configs += [ "//build/config/compiler:enable_arc" ]
   sources = [
     "collection_view_controller.h",
     "collection_view_controller.mm",

ios/chrome/browser/ui/collection_view/collection_view_controller.h

@@ -25,7 +25,7 @@ typedef NS_ENUM(NSInteger, CollectionViewControllerStyle) {
     : MDCCollectionViewController<AppBarPresenting>
 
 // The model of this controller.
-@property(nonatomic, readonly)
+@property(strong, nonatomic, readonly)
     CollectionViewModel<CollectionViewItem*>* collectionViewModel;
 
 // Initializer with the desired style.

ios/chrome/browser/ui/collection_view/collection_view_controller.mm

@@ -6,28 +6,29 @@
 
 #include "base/logging.h"
 #include "base/mac/foundation_util.h"
-#import "base/mac/scoped_nsobject.h"
 #import "ios/chrome/browser/ui/collection_view/cells/collection_view_item.h"
 #import "ios/chrome/browser/ui/collection_view/collection_view_model.h"
 #import "ios/chrome/browser/ui/material_components/utils.h"
 #import "ios/third_party/material_components_ios/src/components/AppBar/src/MaterialAppBar.h"
 #import "ios/third_party/material_components_ios/src/components/CollectionCells/src/MaterialCollectionCells.h"
 
-@implementation CollectionViewController {
-  // The implementation of this controller follows the guidelines from
-  // https://github.com/material-components/material-components-ios/tree/develop/components/AppBar
-  base::scoped_nsobject<MDCAppBar> _appBar;
-  base::scoped_nsobject<CollectionViewModel> _collectionViewModel;
-}
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
+// The implementation of this controller follows the guidelines from
+// https://github.com/material-components/material-components-ios/tree/develop/components/AppBar
+@implementation CollectionViewController
+@synthesize appBar = _appBar;
+@synthesize collectionViewModel = _collectionViewModel;
 
 - (instancetype)initWithStyle:(CollectionViewControllerStyle)style {
-  UICollectionViewLayout* layout =
-      [[[MDCCollectionViewFlowLayout alloc] init] autorelease];
+  UICollectionViewLayout* layout = [[MDCCollectionViewFlowLayout alloc] init];
   self = [super initWithCollectionViewLayout:layout];
   if (self) {
     if (style == CollectionViewControllerStyleAppBar) {
-      _appBar.reset([[MDCAppBar alloc] init]);
-      [self addChildViewController:_appBar.get().headerViewController];
+      _appBar = [[MDCAppBar alloc] init];
+      [self addChildViewController:_appBar.headerViewController];
     }
   }
   return self;
@@ -56,16 +57,8 @@
   return self.appBar.headerViewController;
 }
 
-- (MDCAppBar*)appBar {
-  return _appBar.get();
-}
-
-- (CollectionViewModel*)collectionViewModel {
-  return _collectionViewModel.get();
-}
-
 - (void)loadModel {
-  _collectionViewModel.reset([[CollectionViewModel alloc] init]);
+  _collectionViewModel = [[CollectionViewModel alloc] init];
 }
 
 - (void)reconfigureCellsForItems:(NSArray*)items
@@ -121,8 +114,8 @@
   DCHECK(![MDCCollectionViewController instancesRespondToSelector:_cmd]);
 
   // Retain the item to be able to move it.
-  base::scoped_nsobject<CollectionViewItem> item(
-      [[self.collectionViewModel itemAtIndexPath:indexPath] retain]);
+  CollectionViewItem* item =
+      [self.collectionViewModel itemAtIndexPath:indexPath];
 
   // Item coordinates.
   NSInteger sectionIdentifier =

ios/chrome/browser/ui/collection_view/collection_view_model.mm

@@ -5,33 +5,34 @@
 #import "ios/chrome/browser/ui/collection_view/collection_view_model.h"
 
 #include "base/logging.h"
-#include "base/mac/scoped_nsobject.h"
 #import "ios/chrome/browser/ui/collection_view/cells/collection_view_item.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 typedef NSMutableArray<CollectionViewItem*> SectionItems;
 }
 
 @implementation CollectionViewModel {
   // Ordered list of section identifiers, one per section in the model.
-  base::scoped_nsobject<NSMutableArray<NSNumber*>> _sectionIdentifiers;
+  NSMutableArray<NSNumber*>* _sectionIdentifiers;
 
   // The lists of section items, one per section.
-  base::scoped_nsobject<NSMutableArray<SectionItems*>> _sections;
+  NSMutableArray<SectionItems*>* _sections;
 
   // Maps from section identifier to header and footer.
-  base::scoped_nsobject<NSMutableDictionary<NSNumber*, CollectionViewItem*>>
-      _headers;
-  base::scoped_nsobject<NSMutableDictionary<NSNumber*, CollectionViewItem*>>
-      _footers;
+  NSMutableDictionary<NSNumber*, CollectionViewItem*>* _headers;
+  NSMutableDictionary<NSNumber*, CollectionViewItem*>* _footers;
 }
 
 - (instancetype)init {
   if ((self = [super init])) {
-    _sectionIdentifiers.reset([[NSMutableArray alloc] init]);
-    _sections.reset([[NSMutableArray alloc] init]);
-    _headers.reset([[NSMutableDictionary alloc] init]);
-    _footers.reset([[NSMutableDictionary alloc] init]);
+    _sectionIdentifiers = [[NSMutableArray alloc] init];
+    _sections = [[NSMutableArray alloc] init];
+    _headers = [[NSMutableDictionary alloc] init];
+    _footers = [[NSMutableDictionary alloc] init];
   }
   return self;
 }
@@ -44,7 +45,7 @@ typedef NSMutableArray<CollectionViewItem*> SectionItems;
             [self internalSectionForIdentifier:sectionIdentifier]);
   [_sectionIdentifiers addObject:@(sectionIdentifier)];
 
-  base::scoped_nsobject<SectionItems> section([[SectionItems alloc] init]);
+  SectionItems* section = [[SectionItems alloc] init];
   [_sections addObject:section];
 }
 
@@ -57,7 +58,7 @@ typedef NSMutableArray<CollectionViewItem*> SectionItems;
 
   [_sectionIdentifiers insertObject:@(sectionIdentifier) atIndex:index];
 
-  base::scoped_nsobject<SectionItems> section([[SectionItems alloc] init]);
+  SectionItems* section = [[SectionItems alloc] init];
   [_sections insertObject:section atIndex:index];
 }