Adds button accessibility traits to the nativeAppItem cell.

ios/chrome/browser/ui/settings/cells/native_app_item.mm

 // Copyright 2016 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/settings/cells/native_app_item.h"
 
 #import <QuartzCore/QuartzCore.h>
 
 #import "ios/chrome/browser/ui/colors/MDCPalette+CrAdditions.h"
 #include "ios/chrome/grit/ios_strings.h"
@@ skipping 55 matching lines @@
 
 @synthesize nameLabel = _nameLabel;
 @synthesize iconImageView = _iconImageView;
 @synthesize switchControl = _switchControl;
 @synthesize installButton = _installButton;
 
 - (instancetype)initWithFrame:(CGRect)frame {
   self = [super initWithFrame:frame];
   if (self) {
     UIView* contentView = self.contentView;
+    self.isAccessibilityElement = YES;
 
     _iconImageView = [[UIImageView alloc] init];
     _iconImageView.translatesAutoresizingMaskIntoConstraints = NO;
     _iconImageView.image = PlaceholderIcon();
     _iconImageView.layer.cornerRadius = kIconCornerRadius;
     _iconImageView.layer.masksToBounds = YES;
     self.layer.shouldRasterize = YES;
     self.layer.rasterizationScale = [[UIScreen mainScreen] scale];
     [contentView addSubview:_iconImageView];
 
     _nameLabel = [[UILabel alloc] init];
     _nameLabel.translatesAutoresizingMaskIntoConstraints = NO;
     [contentView addSubview:_nameLabel];
 
     _nameLabel.font =
         [[MDFRobotoFontLoader sharedInstance] mediumFontOfSize:14];
     _nameLabel.textColor = [[MDCPalette greyPalette] tint900];
 
     _switchControl = [[UISwitch alloc] init];
     _switchControl.onTintColor = [[MDCPalette cr_bluePalette] tint500];
 
     _installButton = [[MDCFlatButton alloc] init];
     _installButton.translatesAutoresizingMaskIntoConstraints = NO;
     _installButton.customTitleColor = [[MDCPalette cr_bluePalette] tint500];
     [_installButton
         setTitle:l10n_util::GetNSString(IDS_IOS_GOOGLE_APPS_INSTALL_BUTTON)
         forState:UIControlStateNormal];
     [_installButton setTitle:@"" forState:UIControlStateDisabled];
     _installButton.accessibilityHint = l10n_util::GetNSString(

[lpromero, 2017/01/06 09:41:27]

If the parent view is accessibility element, the button is not visible nor read
by VoiceOver. You need to add this hint to the cell instead (line 171).

[sczs, 2017/01/06 21:59:08]

This currently gets read by VoiceOver since [self.accessoryView
accessibilityHint] returns the installButton accessibilityHint. 

Currently voice over will read: "App Name Install..... Double tap to Install"

         IDS_IOS_GOOGLE_APPS_INSTALL_BUTTON_ACCESSIBILITY_HINT);
 
     // Set up the constraints.
     [NSLayoutConstraint activateConstraints:@[
       [_iconImageView.leadingAnchor
           constraintEqualToAnchor:contentView.leadingAnchor
                          constant:kHorizontalPadding],
       [_iconImageView.trailingAnchor
           constraintEqualToAnchor:_nameLabel.leadingAnchor
                          constant:-kHorizontalPadding],
@@ skipping 49 matching lines @@
   CGRect accessoryViewFrame = UIAccessibilityConvertFrameToScreenCoordinates(
       [self.accessoryView frame], self);
   return CGPointMake(CGRectGetMidX(accessoryViewFrame),
                      CGRectGetMidY(accessoryViewFrame));
 }
 
 - (NSString*)accessibilityHint {
   return [self.accessoryView accessibilityHint];
 }
 
-- (UIAccessibilityTraits)accessibilityTraits {
-  // Remove the "button" accessibility trait from the switch. This matches
-  // native switch content views such as Settings > Airplane Mode.
-  return
-      [super accessibilityTraits] |
-      ([self.switchControl accessibilityTraits] & ~UIAccessibilityTraitButton);
-}
-
 - (NSString*)accessibilityValue {
   if (self.accessoryView == self.switchControl) {
-    return (self.switchControl.on)
-               ? l10n_util::GetNSString(IDS_IOS_SETTING_ON)
-               : l10n_util::GetNSString(IDS_IOS_SETTING_OFF);
+    if (self.switchControl.on) {
+      return [NSString
+          stringWithFormat:@"%@, %@", self.nameLabel.text,
+                           l10n_util::GetNSString(IDS_IOS_SETTING_ON)];
+    } else {
+      return [NSString
+          stringWithFormat:@"%@, %@", self.nameLabel.text,
+                           l10n_util::GetNSString(IDS_IOS_SETTING_OFF)];
+    }
   }
-  return [self.accessoryView accessibilityValue];
+
+  return [NSString stringWithFormat:@"%@, %@", self.nameLabel.text,
+                                    l10n_util::GetNSString(
+                                        IDS_IOS_GOOGLE_APPS_INSTALL_BUTTON)];
 }
 
 @end