Reland of [ObjC ARC] Converts ios/chrome/browser/ui/contextual_search:contextual_search to ARC.

ios/chrome/browser/ui/contextual_search/contextual_search_header_view.mm

 // Copyright 2014 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/contextual_search/contextual_search_header_view.h"
 
-#import "base/ios/weak_nsobject.h"
 #include "base/logging.h"
 #include "base/mac/scoped_cftyperef.h"
-#include "base/mac/scoped_nsobject.h"
 #import "ios/chrome/browser/ui/contextual_search/contextual_search_panel_view.h"
 #import "ios/chrome/browser/ui/uikit_ui_util.h"
 #import "ios/chrome/common/material_timing.h"
 #include "ios/chrome/common/string_util.h"
 #include "ios/public/provider/chrome/browser/chrome_browser_provider.h"
 #include "ios/public/provider/chrome/browser/images/branded_image_provider.h"
 #import "ios/third_party/material_components_ios/src/components/Typography/src/MaterialTypography.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace {
 const CGFloat kHorizontalMargin = 24.0;
 const CGFloat kHorizontalLayoutGap = 16.0;
 
 const NSTimeInterval kTextTransformAnimationDuration =
     ios::material::kDuration1;
 const NSTimeInterval kLogoIrisAnimationDuration = ios::material::kDuration1;
 }  // namespace
 
 // An image that can "iris" in/out. Assumes a square image and will do a stupid-
@@ skipping 69 matching lines @@
   CGFloat _height;
   // Circular logo positioned leading side.
   __unsafe_unretained IrisingImageView* _logo;
   // Up/down caret positioned trailing side.
   __unsafe_unretained UIImageView* _caret;
   // Close control position identically to the caret.
   __unsafe_unretained TappableButton* _closeButton;
   // Label showing the text the user tapped on in the web page, and any
   // additional context that will be displayed.
   __unsafe_unretained UILabel* _textLabel;
-  base::WeakNSProtocol<id<ContextualSearchPanelTapHandler>> _tapHandler;
-  base::scoped_nsobject<UIGestureRecognizer> _tapRecognizer;
+  __weak id<ContextualSearchPanelTapHandler> _tapHandler;
+  UIGestureRecognizer* _tapRecognizer;
 }
 
 + (BOOL)requiresConstraintBasedLayout {
   return YES;
 }
 
 - (instancetype)initWithHeight:(CGFloat)height {
   if (!(self = [super initWithFrame:CGRectZero]))
     return nil;
 
   DCHECK(height > 0);
   _height = height;
 
   self.translatesAutoresizingMaskIntoConstraints = NO;
   self.backgroundColor = [UIColor whiteColor];
-  _tapRecognizer.reset([[UITapGestureRecognizer alloc] init]);
+  _tapRecognizer = [[UITapGestureRecognizer alloc] init];
   [self addGestureRecognizer:_tapRecognizer];
   [_tapRecognizer addTarget:self action:@selector(panelWasTapped:)];
 
   UIImage* logoImage = ios::GetChromeBrowserProvider()
                            ->GetBrandedImageProvider()
                            ->GetContextualSearchHeaderImage();
-  _logo = [[[IrisingImageView alloc] initWithImage:logoImage] autorelease];
+  IrisingImageView* logo = [[IrisingImageView alloc] initWithImage:logoImage];
+  _logo = logo;
   _logo.translatesAutoresizingMaskIntoConstraints = NO;
   _logo.iris = 0.0;
 
-  _caret = [[[UIImageView alloc]
-      initWithImage:[UIImage imageNamed:@"expand_less"]] autorelease];
+  UIImageView* caret =
+      [[UIImageView alloc] initWithImage:[UIImage imageNamed:@"expand_less"]];
+  _caret = caret;
   _caret.translatesAutoresizingMaskIntoConstraints = NO;
   [_caret setContentHuggingPriority:UILayoutPriorityDefaultHigh
                             forAxis:UILayoutConstraintAxisVertical];
   [_caret setContentHuggingPriority:UILayoutPriorityDefaultHigh
                             forAxis:UILayoutConstraintAxisHorizontal];
 
-  _closeButton =
-      [[[TappableButton alloc] initWithFrame:CGRectZero] autorelease];
+  TappableButton* closeButton =
+      [[TappableButton alloc] initWithFrame:CGRectZero];
+  _closeButton = closeButton;
   _closeButton.translatesAutoresizingMaskIntoConstraints = NO;
   [_closeButton setImage:[UIImage imageNamed:@"card_close_button"]
                 forState:UIControlStateNormal];
   [_closeButton setImage:[UIImage imageNamed:@"card_close_button_pressed"]
                 forState:UIControlStateHighlighted];
   [_closeButton setContentHuggingPriority:UILayoutPriorityDefaultHigh
                                   forAxis:UILayoutConstraintAxisVertical];
   [_closeButton setContentHuggingPriority:UILayoutPriorityDefaultHigh
                                   forAxis:UILayoutConstraintAxisHorizontal];
   _closeButton.alpha = 0;
 
-  _textLabel = [[[UILabel alloc] initWithFrame:CGRectZero] autorelease];
+  UILabel* textLabel = [[UILabel alloc] initWithFrame:CGRectZero];
+  _textLabel = textLabel;
   _textLabel.translatesAutoresizingMaskIntoConstraints = NO;
   _textLabel.font = [MDCTypography subheadFont];
   _textLabel.textAlignment = NSTextAlignmentNatural;
   _textLabel.lineBreakMode = NSLineBreakByCharWrapping;
   // Ensure that |_textLabel| doesn't expand past the space defined for it
   // regardless of how long its text is.
   [_textLabel setContentHuggingPriority:UILayoutPriorityDefaultLow
                                 forAxis:UILayoutConstraintAxisHorizontal];
 
   [self setAccessibilityIdentifier:@"header"];
@@ skipping 52 matching lines @@
 }
 
 #pragma mark - property implementation.
 
 - (void)setTapHandler:(id<ContextualSearchPanelTapHandler>)tapHandler {
   if (_tapHandler) {
     [_closeButton removeTarget:_tapHandler
                         action:@selector(closePanel)
               forControlEvents:UIControlEventTouchUpInside];
   }
-  _tapHandler.reset(tapHandler);
+  _tapHandler = tapHandler;
   if (_tapHandler) {
     [_closeButton addTarget:_tapHandler
                      action:@selector(closePanel)
            forControlEvents:UIControlEventTouchUpInside];
   }
 }
 
 - (id<ContextualSearchPanelTapHandler>)tapHandler {
   return _tapHandler;
 }
@@ skipping 54 matching lines @@
   _caret.alpha = caretGradation * caretGradation;
   _closeButton.alpha = closeGradation * closeGradation;
 }
 
 #pragma mark - Animated transitions
 
 - (void)setText:(NSString*)text
     followingTextRange:(NSRange)followingTextRange
               animated:(BOOL)animated {
   NSMutableAttributedString* styledText =
-      [[[NSMutableAttributedString alloc] initWithString:text] autorelease];
+      [[NSMutableAttributedString alloc] initWithString:text];
   [styledText addAttribute:NSForegroundColorAttributeName
                      value:[UIColor colorWithWhite:0 alpha:0.71f]
                      range:followingTextRange];
 
   void (^transform)(void) = ^{
     _textLabel.attributedText = styledText;
   };
   void (^complete)(BOOL) = ^(BOOL finished) {
     [self showLogoAnimated:animated];
   };
@@ skipping 70 matching lines @@
                              curve:ios::material::CurveEaseOut
                            options:0
                         animations:transform
                         completion:nil];
   } else {
     transform();
   }
 }
 
 @end