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

ios/chrome/browser/ui/side_swipe/side_swipe_navigation_view.mm

Index: ios/chrome/browser/ui/side_swipe/side_swipe_navigation_view.mm
diff --git a/ios/chrome/browser/ui/side_swipe/side_swipe_navigation_view.mm b/ios/chrome/browser/ui/side_swipe/side_swipe_navigation_view.mm
index ca4fa6d282be5e5ccc09230ff1ef18b843b1dabe..83beea7ef9b01c8315f3795d1419addf40aa9c81 100644
--- a/ios/chrome/browser/ui/side_swipe/side_swipe_navigation_view.mm
+++ b/ios/chrome/browser/ui/side_swipe/side_swipe_navigation_view.mm
@@ -7,8 +7,7 @@
 #include <cmath>
 
 #include "base/logging.h"
-#include "base/mac/objc_property_releaser.h"
-#include "base/mac/scoped_nsobject.h"
+
 #include "base/metrics/user_metrics.h"
 #include "base/metrics/user_metrics_action.h"
 #import "ios/chrome/browser/ui/side_swipe/side_swipe_util.h"
@@ -17,6 +16,10 @@
 #import "ios/chrome/browser/ui/uikit_ui_util.h"
 #import "ios/chrome/common/material_timing.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 
 enum class SwipeType { CHANGE_TABS, NAVIGATION };
@@ -71,7 +74,7 @@ const CGFloat kSelectionAnimationDuration = 0.5;
   BOOL thresholdTriggered_;
 
   // The back or forward sprite image.
-  base::scoped_nsobject<UIImageView> arrowView_;
+  UIImageView* arrowView_;
 
   // The selection bubble.
   CAShapeLayer* selectionCircleLayer_;
@@ -83,8 +86,6 @@ const CGFloat kSelectionAnimationDuration = 0.5;
   // If |YES| arrowView_ is directionnal and must be rotated 180 degreed for the
   // forward panes.
   BOOL rotateForward_;
-
-  base::mac::ObjCPropertyReleaser _propertyReleaser_SideSwipeNavigationView;
 }
 // Returns a newly allocated and configured selection circle shape.
 - (CAShapeLayer*)newSelectionCircleLayer;
@@ -104,8 +105,6 @@ const CGFloat kSelectionAnimationDuration = 0.5;
                 rotateForward:(BOOL)rotateForward {
   self = [super initWithFrame:frame];
   if (self) {
-    _propertyReleaser_SideSwipeNavigationView.Init(
-        self, [SideSwipeNavigationView class]);
     self.backgroundColor = [UIColor colorWithWhite:90.0 / 256 alpha:1.0];
 
     canNavigate_ = canNavigate;
@@ -113,7 +112,7 @@ const CGFloat kSelectionAnimationDuration = 0.5;
     if (canNavigate) {
       image = [image imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
       const CGRect imageSize = CGRectMake(0, 0, 24, 24);
-      arrowView_.reset([[UIImageView alloc] initWithImage:image]);
+      arrowView_ = [[UIImageView alloc] initWithImage:image];
       [arrowView_ setTintColor:[UIColor whiteColor]];
       selectionCircleLayer_ = [self newSelectionCircleLayer];
       [arrowView_ setFrame:imageSize];
@@ -123,8 +122,7 @@ const CGFloat kSelectionAnimationDuration = 0.5;
         [UIImage imageNamed:@"side_swipe_navigation_content_shadow"];
     CGRect borderFrame =
         CGRectMake(0, 0, shadowImage.size.width, self.frame.size.height);
-    base::scoped_nsobject<UIImageView> border(
-        [[UIImageView alloc] initWithFrame:borderFrame]);
+    UIImageView* border = [[UIImageView alloc] initWithFrame:borderFrame];
     [border setImage:shadowImage];
     [self addSubview:border];
     if (direction == UISwipeGestureRecognizerDirectionRight) {