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

ios/chrome/browser/ui/tab_switcher/tab_switcher_controller.mm

Index: ios/chrome/browser/ui/tab_switcher/tab_switcher_controller.mm
diff --git a/ios/chrome/browser/ui/tab_switcher/tab_switcher_controller.mm b/ios/chrome/browser/ui/tab_switcher/tab_switcher_controller.mm
index 502ca999b4879314f9fad173413e4af586913740..f6c72267b6d0db115e72a72019e955de9da51e83 100644
--- a/ios/chrome/browser/ui/tab_switcher/tab_switcher_controller.mm
+++ b/ios/chrome/browser/ui/tab_switcher/tab_switcher_controller.mm
@@ -5,8 +5,6 @@
 #import "ios/chrome/browser/ui/tab_switcher/tab_switcher_controller.h"
 
 #include "base/ios/block_types.h"
-#include "base/ios/weak_nsobject.h"
-#include "base/mac/scoped_nsobject.h"
 #include "base/metrics/user_metrics.h"
 #include "base/metrics/user_metrics_action.h"
 #include "base/strings/sys_string_conversions.h"
@@ -53,6 +51,10 @@
 #include "ui/base/l10n/l10n_util.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 {
 
 // Offsets for computing the panels' indexes in the TabSwitcherView.
@@ -91,21 +93,21 @@ enum class SnapshotViewOption {
   // weak.
   TabModel* _onLoadActiveModel;
   // The view this controller manages.
-  base::scoped_nsobject<TabSwitcherView> _tabSwitcherView;
+  TabSwitcherView* _tabSwitcherView;
   // The list of panels controllers for distant sessions.
-  base::scoped_nsobject<NSMutableArray> _controllersOfDistantSessions;
+  NSMutableArray* _controllersOfDistantSessions;
   // The panel controllers for the local sessions.
-  base::scoped_nsobject<TabSwitcherPanelController> _onTheRecordSession;
-  base::scoped_nsobject<TabSwitcherPanelController> _offTheRecordSession;
+  TabSwitcherPanelController* _onTheRecordSession;
+  TabSwitcherPanelController* _offTheRecordSession;
   // The model storing the state of what is shown by the tab switcher.
-  base::scoped_nsobject<TabSwitcherModel> _tabSwitcherModel;
+  TabSwitcherModel* _tabSwitcherModel;
   // Stores the current sign-in panel type.
   TabSwitcherSignInPanelsType _signInPanelType;
   // Cache for the panel's cells.
-  base::scoped_nsobject<TabSwitcherCache> _cache;
+  TabSwitcherCache* _cache;
   // Stores the background color of the window when the tab switcher was
   // presented.
-  base::scoped_nsobject<UIColor> _initialWindowBackgroundColor;
+  UIColor* _initialWindowBackgroundColor;
   // Indicate whether a previous promo panel header cell should be removed or
   // added.
   BOOL _shouldRemovePromoPanelHeaderCell;
@@ -193,27 +195,27 @@ enum class SnapshotViewOption {
   if (self) {
     _browserState = browserState;
     _onLoadActiveModel = activeTabModel;
-    _cache.reset([[TabSwitcherCache alloc] init]);
+    _cache = [[TabSwitcherCache alloc] init];
     [_cache setMainTabModel:mainTabModel otrTabModel:otrTabModel];
-    _tabSwitcherModel.reset([[TabSwitcherModel alloc]
-        initWithBrowserState:browserState
-                    delegate:self
-                mainTabModel:mainTabModel
-                 otrTabModel:otrTabModel
-                   withCache:_cache]);
-    _controllersOfDistantSessions.reset([[NSMutableArray alloc] init]);
+    _tabSwitcherModel =
+        [[TabSwitcherModel alloc] initWithBrowserState:browserState
+                                              delegate:self
+                                          mainTabModel:mainTabModel
+                                           otrTabModel:otrTabModel
+                                             withCache:_cache];
+    _controllersOfDistantSessions = [[NSMutableArray alloc] init];
     [self loadTabSwitcherView];
-    _onTheRecordSession.reset([[TabSwitcherPanelController alloc]
+    _onTheRecordSession = [[TabSwitcherPanelController alloc]
                 initWithModel:_tabSwitcherModel
         forLocalSessionOfType:TabSwitcherSessionType::REGULAR_SESSION
                     withCache:_cache
-                 browserState:_browserState]);
+                 browserState:_browserState];
     [_onTheRecordSession setDelegate:self];
-    _offTheRecordSession.reset([[TabSwitcherPanelController alloc]
+    _offTheRecordSession = [[TabSwitcherPanelController alloc]
                 initWithModel:_tabSwitcherModel
         forLocalSessionOfType:TabSwitcherSessionType::OFF_THE_RECORD_SESSION
                     withCache:_cache
-                 browserState:_browserState]);
+                 browserState:_browserState];
     [_offTheRecordSession setDelegate:self];
     [_tabSwitcherView addPanelView:[_offTheRecordSession view]
                            atIndex:kLocalTabsOffTheRecordPanelIndex];
@@ -243,8 +245,8 @@ enum class SnapshotViewOption {
 
 - (void)loadTabSwitcherView {
   DCHECK(![_tabSwitcherView superview]);
-  _tabSwitcherView.reset(
-      [[TabSwitcherView alloc] initWithFrame:[self tabSwitcherInitialFrame]]);
+  _tabSwitcherView =
+      [[TabSwitcherView alloc] initWithFrame:[self tabSwitcherInitialFrame]];
   [_tabSwitcherView setAutoresizingMask:UIViewAutoresizingFlexibleWidth |
                                         UIViewAutoresizingFlexibleHeight];
   [_tabSwitcherView setDelegate:self];
@@ -263,7 +265,7 @@ enum class SnapshotViewOption {
 #pragma mark - UIResponder
 
 - (NSArray*)keyCommands {
-  base::WeakNSObject<TabSwitcherController> weakSelf(self);
+  __weak TabSwitcherController* weakSelf = self;
   return @[
     [UIKeyCommand
         cr_keyCommandWithInput:@"t"
@@ -271,8 +273,7 @@ enum class SnapshotViewOption {
                          title:l10n_util::GetNSStringWithFixup(
                                    IDS_IOS_TOOLS_MENU_NEW_TAB)
                         action:^{
-                          base::scoped_nsobject<TabSwitcherController>
-                              strongSelf([weakSelf retain]);
+                          TabSwitcherController* strongSelf = weakSelf;
                           if (!strongSelf)
                             return;
                           if ([strongSelf currentPanelIndex] ==
@@ -306,8 +307,7 @@ enum class SnapshotViewOption {
                  modifierFlags:UIKeyModifierCommand
                          title:nil
                         action:^{
-                          base::scoped_nsobject<TabSwitcherController>
-                              strongSelf([weakSelf retain]);
+                          TabSwitcherController* strongSelf = weakSelf;
                           if (!strongSelf)
                             return;
                           if ([strongSelf currentPanelIndex] ==
@@ -414,14 +414,13 @@ enum class SnapshotViewOption {
 
 - (void)updateWindowBackgroundColor {
   DCHECK(!_initialWindowBackgroundColor);
-  _initialWindowBackgroundColor.reset(
-      [self.view.window.backgroundColor retain]);
+  _initialWindowBackgroundColor = self.view.window.backgroundColor;
   self.view.window.backgroundColor = [[MDCPalette greyPalette] tint900];
 }
 
 - (void)restoreWindowBackgroundColor {
   self.view.window.backgroundColor = _initialWindowBackgroundColor;
-  _initialWindowBackgroundColor.reset();
+  _initialWindowBackgroundColor = nil;
 }
 
 - (UIView*)snapshotViewForView:(UIView*)inputView
@@ -442,7 +441,7 @@ enum class SnapshotViewOption {
     [inputView.layer renderInContext:UIGraphicsGetCurrentContext()];
     UIImage* screenshot = UIGraphicsGetImageFromCurrentImageContext();
     UIGraphicsEndImageContext();
-    UIView* view = [[[UIView alloc] initWithFrame:CGRectZero] autorelease];
+    UIView* view = [[UIView alloc] initWithFrame:CGRectZero];
     [view layer].contents = static_cast<id>(screenshot.CGImage);
     return view;
   } else {
@@ -451,8 +450,7 @@ enum class SnapshotViewOption {
     UIColor* backgroundColor = [tabModel isOffTheRecord]
                                    ? [[MDCPalette greyPalette] tint700]
                                    : [[MDCPalette greyPalette] tint100];
-    UIView* placeholdView =
-        [[[UIView alloc] initWithFrame:CGRectZero] autorelease];
+    UIView* placeholdView = [[UIView alloc] initWithFrame:CGRectZero];
     placeholdView.backgroundColor = backgroundColor;
     return placeholdView;
   }
@@ -561,28 +559,26 @@ enum class SnapshotViewOption {
   CGRect finalToolbarScreenshotFrame =
       CGRectMake(0, 0, selectedCellFrame.size.width, cellTopBarHeight);
 
-  base::scoped_nsobject<UIImageView> tabScreenshotImageView(
-      [[UIImageView alloc] initWithFrame:CGRectZero]);
+  UIImageView* tabScreenshotImageView =
+      [[UIImageView alloc] initWithFrame:CGRectZero];
 
-  base::WeakNSObject<UIImageView> weakTabScreenshotImageView(
-      tabScreenshotImageView.get());
+  __weak UIImageView* weakTabScreenshotImageView = tabScreenshotImageView;
 
   if ([self initialTabModelAndTabIDMatchesTabModel:tabModel
                                              tabID:selectedTab.tabId]) {
-    tabScreenshotImageView.get().image =
-        self.transitionContext.tabSnapshotImage;
+    tabScreenshotImageView.image = self.transitionContext.tabSnapshotImage;
   } else {
     // If transitioning to a different tab than the one animated in
     // from, a new snapshot should be generated instead of using the transition
     // context
-    tabScreenshotImageView.get().image =
+    tabScreenshotImageView.image =
         [self updateScreenshotForCellIfNeeded:selectedCell tabModel:tabModel];
     [selectedTab retrieveSnapshot:^(UIImage* snapshot) {
       [weakTabScreenshotImageView setImage:snapshot];
     }];
   }
 
-  const CGSize tabScreenshotImageSize = tabScreenshotImageView.get().image.size;
+  const CGSize tabScreenshotImageSize = tabScreenshotImageView.image.size;
 
   CGRect initialTabScreenshotFrame = CGRectZero;
   const CGSize toolbarSize = toolbarController.view.bounds.size;
@@ -640,14 +636,13 @@ enum class SnapshotViewOption {
   tabStripPlaceholderView.frame = tabStripInitialFrame;
 
   // Create and setup placeholder view and subviews.
-  base::scoped_nsobject<UIView> placeholderView(
-      [[UIView alloc] initWithFrame:initialTabFrame]);
+  UIView* placeholderView = [[UIView alloc] initWithFrame:initialTabFrame];
   [placeholderView setClipsToBounds:YES];
   [placeholderView setUserInteractionEnabled:NO];
 
-  tabScreenshotImageView.get().frame = initialTabScreenshotFrame;
-  tabScreenshotImageView.get().contentMode = UIViewContentModeScaleToFill;
-  tabScreenshotImageView.get().autoresizingMask = UIViewAutoresizingNone;
+  tabScreenshotImageView.frame = initialTabScreenshotFrame;
+  tabScreenshotImageView.contentMode = UIViewContentModeScaleToFill;
+  tabScreenshotImageView.autoresizingMask = UIViewAutoresizingNone;
   [placeholderView addSubview:tabScreenshotImageView];
 
   // Try using a snapshot view for dismissal animation because it's faster and
@@ -671,8 +666,8 @@ enum class SnapshotViewOption {
   toolbarScreenshotImageView.frame = initialToolbarScreenshotFrame;
   [placeholderView addSubview:toolbarScreenshotImageView];
 
-  base::scoped_nsobject<UIImageView> toolbarShadowImageView(
-      [[UIImageView alloc] initWithFrame:shadowInitialFrame]);
+  UIImageView* toolbarShadowImageView =
+      [[UIImageView alloc] initWithFrame:shadowInitialFrame];
   [toolbarShadowImageView setAutoresizingMask:UIViewAutoresizingNone];
   [toolbarShadowImageView setImage:NativeImage(IDR_IOS_TOOLBAR_SHADOW)];
   [placeholderView addSubview:toolbarShadowImageView];
@@ -683,9 +678,9 @@ enum class SnapshotViewOption {
   toolbarScreenshotImageView.alpha =
       (transitionType == TransitionType::TRANSITION_DISMISS) ? 0 : 1.0;
 
-  base::WeakNSObject<TabSwitcherController> weakSelf(self);
+  __weak TabSwitcherController* weakSelf = self;
   void (^completionBlock)(BOOL) = ^(BOOL finished) {
-    base::scoped_nsobject<TabSwitcherController> strongSelf([weakSelf retain]);
+    TabSwitcherController* strongSelf = weakSelf;
 
     [tabStripPlaceholderView removeFromSuperview];
     [toolbarScreenshotImageView removeFromSuperview];
@@ -708,11 +703,11 @@ enum class SnapshotViewOption {
     toolbarScreenshotImageView.alpha =
         transitionType == TransitionType::TRANSITION_DISMISS ? 1.0 : 0;
     tabStripPlaceholderView.frame = tabStripFinalFrame;
-    toolbarShadowImageView.get().frame = shadowFinalFrame;
-    placeholderView.get().frame = finalTabFrame;
+    toolbarShadowImageView.frame = shadowFinalFrame;
+    placeholderView.frame = finalTabFrame;
     toolbarScreenshotImageView.frame = finalToolbarScreenshotFrame;
     finalToolbarScreenshotImageView.frame = finalToolbarScreenshotFrame;
-    tabScreenshotImageView.get().frame = finalTabScreenshotFrame;
+    tabScreenshotImageView.frame = finalTabScreenshotFrame;
   };
 
   [UIView animateWithDuration:animated ? kTransitionAnimationDuration : 0
@@ -796,9 +791,9 @@ enum class SnapshotViewOption {
   DCHECK(tabModel == [_tabSwitcherModel mainTabModel] ||
          tabModel == [_tabSwitcherModel otrTabModel]);
   if (tabModel == [_tabSwitcherModel mainTabModel])
-    return _onTheRecordSession.get();
+    return _onTheRecordSession;
   if (tabModel == [_tabSwitcherModel otrTabModel])
-    return _offTheRecordSession.get();
+    return _offTheRecordSession;
   return nil;
 }
 
@@ -956,15 +951,14 @@ enum class SnapshotViewOption {
   for (NSNumber* objCIndex in insertedIndexes) {
     int index = [objCIndex intValue];
     std::string tag = [_tabSwitcherModel tagOfDistantSessionAtIndex:index];
-    base::scoped_nsobject<TabSwitcherPanelController> panelController(
+    TabSwitcherPanelController* panelController =
         [[TabSwitcherPanelController alloc] initWithModel:_tabSwitcherModel
                                  forDistantSessionWithTag:tag
-                                             browserState:_browserState]);
+                                             browserState:_browserState];
     [panelController setDelegate:self];
     [_tabSwitcherView addPanelView:[panelController view]
                            atIndex:index + offset];
-    [_controllersOfDistantSessions insertObject:panelController.get()
-                                        atIndex:index];
+    [_controllersOfDistantSessions insertObject:panelController atIndex:index];
   }
 
   // Update the header view.
@@ -973,8 +967,7 @@ enum class SnapshotViewOption {
 }
 
 - (void)distantSessionMayNeedUpdate:(std::string const&)tag {
-  for (TabSwitcherPanelController* panel in _controllersOfDistantSessions
-           .get()) {
+  for (TabSwitcherPanelController* panel in _controllersOfDistantSessions) {
     DCHECK([panel isKindOfClass:[TabSwitcherPanelController class]]);
     if ([panel sessionTag] == tag) {
       [panel updateCollectionViewIfNeeded];
@@ -1013,9 +1006,8 @@ enum class SnapshotViewOption {
   _signInPanelType = panelType;
   if (panelType != TabSwitcherSignInPanelsType::NO_PANEL) {
     TabSwitcherPanelOverlayView* panelView =
-        [[[TabSwitcherPanelOverlayView alloc] initWithFrame:CGRectZero
-                                               browserState:_browserState]
-            autorelease];
+        [[TabSwitcherPanelOverlayView alloc] initWithFrame:CGRectZero
+                                              browserState:_browserState];
     [panelView setOverlayType:PanelOverlayTypeFromSignInPanelsType(panelType)];
     [_tabSwitcherView addPanelView:panelView atIndex:kSignInPromoPanelIndex];
   }
@@ -1082,7 +1074,7 @@ enum class SnapshotViewOption {
           sync_sessions::SyncedSession::TYPE_UNSET;
       NSString* cellTitle = nil;
 
-      if (index < _controllersOfDistantSessions.get().count) {
+      if (index < _controllersOfDistantSessions.count) {
         TabSwitcherPanelController* panel =
             [_controllersOfDistantSessions objectAtIndex:index];
         const synced_sessions::DistantSession* distantSession =
@@ -1103,8 +1095,7 @@ enum class SnapshotViewOption {
           break;
       }
       TabSwitcherSessionCellData* sessionData =
-          [[[TabSwitcherSessionCellData alloc] initWithSessionCellType:cellType]
-              autorelease];
+          [[TabSwitcherSessionCellData alloc] initWithSessionCellType:cellType];
       sessionData.title = cellTitle;
       return sessionData;
     }
@@ -1131,8 +1122,8 @@ enum class SnapshotViewOption {
         base::UserMetricsAction("MobileTabSwitcherCreateNonIncognitoTab"));
   }
   // Create and execute command to create the tab.
-  base::scoped_nsobject<GenericChromeCommand> command(
-      [[GenericChromeCommand alloc] initWithTag:tag]);
+  GenericChromeCommand* command =
+      [[GenericChromeCommand alloc] initWithTag:tag];
   [self chromeExecuteCommand:command];
 }