TableCaptionElement is not exposed to accessibility

ui/accessibility/platform/ax_platform_node_mac.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 "ui/accessibility/platform/ax_platform_node_mac.h"
 
 #import <Cocoa/Cocoa.h>
 
 #include "base/strings/sys_string_conversions.h"
 #import "ui/accessibility/platform/ax_platform_node_delegate.h"
@@ skipping 13 matching lines @@
       {ui::AX_ROLE_ALERT, NSAccessibilityGroupRole},
       {ui::AX_ROLE_ALERT_DIALOG, NSAccessibilityGroupRole},
       {ui::AX_ROLE_ANNOTATION, NSAccessibilityUnknownRole},
       {ui::AX_ROLE_APPLICATION, NSAccessibilityGroupRole},
       {ui::AX_ROLE_ARTICLE, NSAccessibilityGroupRole},
       {ui::AX_ROLE_BANNER, NSAccessibilityGroupRole},
       {ui::AX_ROLE_BLOCKQUOTE, NSAccessibilityGroupRole},
       {ui::AX_ROLE_BUSY_INDICATOR, NSAccessibilityBusyIndicatorRole},
       {ui::AX_ROLE_BUTTON, NSAccessibilityButtonRole},
       {ui::AX_ROLE_CANVAS, NSAccessibilityImageRole},
+      {ui::AX_ROLE_CAPTION, NSAccessibilityGroupRole},
       {ui::AX_ROLE_CELL, @"AXCell"},
       {ui::AX_ROLE_CHECK_BOX, NSAccessibilityCheckBoxRole},
       {ui::AX_ROLE_COLOR_WELL, NSAccessibilityColorWellRole},
       {ui::AX_ROLE_COLUMN, NSAccessibilityColumnRole},
       {ui::AX_ROLE_COLUMN_HEADER, @"AXCell"},
       {ui::AX_ROLE_COMBO_BOX, NSAccessibilityComboBoxRole},
       {ui::AX_ROLE_COMPLEMENTARY, NSAccessibilityGroupRole},
       {ui::AX_ROLE_CONTENT_INFO, NSAccessibilityGroupRole},
       {ui::AX_ROLE_DATE, @"AXDateField"},
       {ui::AX_ROLE_DATE_TIME, NSAccessibilityTextFieldRole},
@@ skipping 260 matching lines @@
   delete this;
 }
 
 gfx::NativeViewAccessible AXPlatformNodeMac::GetNativeViewAccessible() {
   if (!native_node_)
     native_node_.reset([[AXPlatformNodeCocoa alloc] initWithNode:this]);
   return native_node_.get();
 }
 
 }  // namespace ui