base::mac::IsOSSierra() -> base::mac::IsOS10_12(), etc.

content/browser/accessibility/browser_accessibility_manager_mac.mm

 // Copyright (c) 2012 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.
 
 #include "content/browser/accessibility/browser_accessibility_manager_mac.h"
 
 #import "base/mac/mac_util.h"
 #import "base/mac/sdk_forward_declarations.h"
 #include "base/logging.h"
 #include "base/strings/sys_string_conversions.h"
@@ skipping 195 matching lines @@
       break;
     case ui::AX_EVENT_DOCUMENT_SELECTION_CHANGED: {
       mac_notification = NSAccessibilitySelectedTextChangedNotification;
       // WebKit fires a notification both on the focused object and the root.
       BrowserAccessibility* focus = GetFocus();
       if (!focus)
         break;  // Just fire a notification on the root.
       NSAccessibilityPostNotification(ToBrowserAccessibilityCocoa(focus),
                                       mac_notification);
 
-      if (base::mac::IsOSElCapitanOrLater()) {
+      if (base::mac::IsAtLeastOS10_11()) {
         // |NSAccessibilityPostNotificationWithUserInfo| should be used on OS X
         // 10.11 or later to notify Voiceover about text selection changes. This
         // API has been present on versions of OS X since 10.7 but doesn't
         // appear to be needed by Voiceover before version 10.11.
         NSDictionary* user_info =
             GetUserInfoForSelectedTextChangedNotification();
 
         BrowserAccessibility* root = GetRoot();
         if (!root)
           return;
 
         NSAccessibilityPostNotificationWithUserInfo(
             ToBrowserAccessibilityCocoa(focus), mac_notification, user_info);
         NSAccessibilityPostNotificationWithUserInfo(
             ToBrowserAccessibilityCocoa(root), mac_notification, user_info);
         return;
       }
       break;
     }
     case ui::AX_EVENT_CHECKED_STATE_CHANGED:
       mac_notification = NSAccessibilityValueChangedNotification;
       break;
     case ui::AX_EVENT_VALUE_CHANGED:
       mac_notification = NSAccessibilityValueChangedNotification;
-      if (base::mac::IsOSElCapitanOrLater() && text_edits_.size()) {
+      if (base::mac::IsAtLeastOS10_11() && text_edits_.size()) {
         // It seems that we don't need to distinguish between deleted and
         // inserted text for now.
         base::string16 deleted_text;
         base::string16 inserted_text;
         int32_t id = node->GetId();
         const auto iterator = text_edits_.find(id);
         if (iterator != text_edits_.end())
           inserted_text = iterator->second;
         NSDictionary* user_info = GetUserInfoForValueChangedNotification(
             native_node, deleted_text, inserted_text);
@@ skipping 213 matching lines @@
   }
 
   return @{
     NSAccessibilityTextStateChangeTypeKey : @(AXTextStateChangeTypeEdit),
     NSAccessibilityTextChangeValues : changes,
     NSAccessibilityTextChangeElement : native_node
   };
 }
 
 }  // namespace content