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

ios/chrome/browser/ui/util/transparent_link_button.mm

 // Copyright 2015 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/util/transparent_link_button.h"
 
 #include "base/ios/ios_util.h"
-#import "base/ios/weak_nsobject.h"
 #import "base/logging.h"
-#import "base/mac/scoped_nsobject.h"
 #import "base/strings/sys_string_conversions.h"
 #include "url/gurl.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 // Minimum tap area dimension, as specified by Apple guidelines.
 const CGFloat kLinkTapAreaMinimum = 44.0;
 
 namespace {
 // The corner radius of the highlight view.
 const CGFloat kHighlightViewCornerRadius = 2.0;
 // The alpha of the highlight view's background color (base color is black).
 const CGFloat kHighlightViewBackgroundAlpha = 0.25;
 }
 
-@interface TransparentLinkButton () {
-  // Backing objects for properties of the same name.
-  base::scoped_nsobject<UIView> _highlightView;
-  base::WeakNSObject<TransparentLinkButton> _previousLinkButton;
-  base::WeakNSObject<TransparentLinkButton> _nextLinkButton;
-}
+@interface TransparentLinkButton ()
 
 // The link frame passed upon initialization.
 @property(nonatomic, readonly) CGRect linkFrame;
 
 // Semi-transparent overlay that is shown to highlight the link text when the
 // button's highlight state is set to YES.
-@property(nonatomic, readonly) UIView* highlightView;
+@property(nonatomic, strong, readonly) UIView* highlightView;
 
 // Links that span multiple lines require more than one TransparentLinkButton.
 // These properties are used to populate the highlight state from one button to
 // the other buttons corresponding with the same link.
 @property(nonatomic, weak) TransparentLinkButton* previousLinkButton;
 @property(nonatomic, weak) TransparentLinkButton* nextLinkButton;
 
 // Designated initializer.  |linkFrame| is the frame of the link text; this may
 // differ from the actual frame of the resulting TransparentLinkButton, which is
 // guaranteed to be at least |kLinkTapAreaMinimum| in each dimension.  |URL| is
@@ skipping 11 matching lines @@
 // state.
 - (void)updateHighlightView;
 
 @end
 
 @implementation TransparentLinkButton
 
 @synthesize URL = _URL;
 @synthesize debug = _debug;
 @synthesize linkFrame = _linkFrame;
+@synthesize highlightView = _highlightView;
+@synthesize previousLinkButton = _previousLinkButton;
+@synthesize nextLinkButton = _nextLinkButton;
 
 - (instancetype)initWithLinkFrame:(CGRect)linkFrame URL:(const GURL&)URL {
   CGFloat linkHeightExpansion =
       MAX(0, (kLinkTapAreaMinimum - linkFrame.size.height) / 2.0);
   CGFloat linkWidthExpansion =
       MAX(0, (kLinkTapAreaMinimum - linkFrame.size.width) / 2.0);
   // Expand the frame as necessary to meet the minimum tap area dimensions.
   CGRect frame =
       CGRectInset(linkFrame, -linkWidthExpansion, -linkHeightExpansion);
   if ((self = [super initWithFrame:frame])) {
     DCHECK(URL.is_valid());
     self.contentEdgeInsets =
         UIEdgeInsetsMake(linkHeightExpansion, linkWidthExpansion,
                          linkHeightExpansion, linkWidthExpansion);
     self.backgroundColor = [UIColor clearColor];
     _linkFrame = linkFrame;
     _URL = URL;
     // These buttons are positioned absolutely based on the the position of
     // regions of text that is already correctly aligned for RTL if necessary.
     self.semanticContentAttribute = UISemanticContentAttributeSpatial;
   }
   return self;
 }
 
 #pragma mark - Accessors
 
-- (void)setPreviousLinkButton:(TransparentLinkButton*)previousLinkButton {
-  _previousLinkButton.reset(previousLinkButton);
-}
-
-- (TransparentLinkButton*)previousLinkButton {
-  return _previousLinkButton.get();
-}
-
-- (void)setNextLinkButton:(TransparentLinkButton*)nextLinkButton {
-  _nextLinkButton.reset(nextLinkButton);
-}
-
-- (TransparentLinkButton*)nextLinkButton {
-  return _nextLinkButton.get();
-}
-
 - (void)setDebug:(BOOL)debug {
   _debug = debug;
   self.layer.borderWidth = _debug ? 1.0 : 0.0;
   self.layer.borderColor =
       _debug ? [UIColor greenColor].CGColor : [UIColor clearColor].CGColor;
   self.backgroundColor = _debug ? [UIColor redColor] : [UIColor clearColor];
   self.alpha = _debug ? 0.15 : 1.0;
 }
 
 - (UIView*)highlightView {
   if (!_highlightView) {
     CGRect linkFrame =
         [self convertRect:self.linkFrame fromView:self.superview];
     linkFrame = CGRectInset(linkFrame, -kHighlightViewCornerRadius, 0);
-    _highlightView.reset([[UIView alloc] initWithFrame:linkFrame]);
+    _highlightView = [[UIView alloc] initWithFrame:linkFrame];
     [_highlightView
         setBackgroundColor:[UIColor
                                colorWithWhite:0.0
                                         alpha:kHighlightViewBackgroundAlpha]];
     [_highlightView layer].cornerRadius = kHighlightViewCornerRadius;
     [_highlightView setClipsToBounds:YES];
     [self addSubview:_highlightView];
   }
-  return _highlightView.get();
+  return _highlightView;
 }
 
 - (void)setHighlighted:(BOOL)highlighted {
   [self setHighlighted:highlighted sender:nil];
 }
 
 - (void)setSelected:(BOOL)selected {
   [self setSelected:selected sender:nil];
 }
 
 #pragma mark -
 
 + (NSArray*)buttonsForLinkFrames:(NSArray*)linkFrames
                              URL:(const GURL&)URL
               accessibilityLabel:(NSString*)label {
   if (!linkFrames.count)
     return @[];
-  base::scoped_nsobject<NSMutableArray> buttons(
-      [[NSMutableArray alloc] initWithCapacity:linkFrames.count]);
+  NSMutableArray* buttons =
+      [[NSMutableArray alloc] initWithCapacity:linkFrames.count];
   for (NSValue* linkFrameValue in linkFrames) {
     CGRect linkFrame = [linkFrameValue CGRectValue];
-    base::scoped_nsobject<TransparentLinkButton> button(
-        [[TransparentLinkButton alloc] initWithLinkFrame:linkFrame URL:URL]);
+    TransparentLinkButton* button =
+        [[TransparentLinkButton alloc] initWithLinkFrame:linkFrame URL:URL];
     TransparentLinkButton* previousButton = [buttons lastObject];
     previousButton.nextLinkButton = button;
     [button setPreviousLinkButton:previousButton];
     // Make buttons not accessible by default, but provide label for tests.
     [button setIsAccessibilityElement:NO];
     [button setAccessibilityLabel:label];
     [buttons addObject:button];
   }
   // Make the first button accessible.
   [buttons[0] setIsAccessibilityElement:YES];
@@ skipping 16 matching lines @@
   if (self.nextLinkButton != sender)
     [self.nextLinkButton setSelected:selected sender:self];
   [self updateHighlightView];
 }
 
 - (void)updateHighlightView {
   self.highlightView.hidden = !self.highlighted && !self.selected;
 }
 
 @end