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

content/browser/accessibility/browser_accessibility_manager_mac.mm

Index: content/browser/accessibility/browser_accessibility_manager_mac.mm
diff --git a/content/browser/accessibility/browser_accessibility_manager_mac.mm b/content/browser/accessibility/browser_accessibility_manager_mac.mm
index b2dff5cf91602e237a02682f2ad1f5baf62a74f6..11b485d794b253b71bc3a9bd2bb547b1b2f6518d 100644
--- a/content/browser/accessibility/browser_accessibility_manager_mac.mm
+++ b/content/browser/accessibility/browser_accessibility_manager_mac.mm
@@ -213,7 +213,7 @@ void BrowserAccessibilityManagerMac::NotifyAccessibilityEvent(
       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
@@ -238,7 +238,7 @@ void BrowserAccessibilityManagerMac::NotifyAccessibilityEvent(
       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;