Expose HTML pre tag with correct MSAA+IA2 Role

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 77 matching lines @@
       {ui::AX_ROLE_MENU_ITEM_RADIO, NSAccessibilityMenuItemRole},
       {ui::AX_ROLE_MENU_LIST_OPTION, NSAccessibilityMenuItemRole},
       {ui::AX_ROLE_MENU_LIST_POPUP, NSAccessibilityUnknownRole},
       {ui::AX_ROLE_METER, NSAccessibilityProgressIndicatorRole},
       {ui::AX_ROLE_NAVIGATION, NSAccessibilityGroupRole},
       {ui::AX_ROLE_NONE, NSAccessibilityGroupRole},
       {ui::AX_ROLE_NOTE, NSAccessibilityGroupRole},
       {ui::AX_ROLE_OUTLINE, NSAccessibilityOutlineRole},
       {ui::AX_ROLE_PARAGRAPH, NSAccessibilityGroupRole},
       {ui::AX_ROLE_POP_UP_BUTTON, NSAccessibilityPopUpButtonRole},
+      {ui::AX_ROLE_PRE, NSAccessibilityGroupRole},
       {ui::AX_ROLE_PRESENTATIONAL, NSAccessibilityGroupRole},
       {ui::AX_ROLE_PROGRESS_INDICATOR, NSAccessibilityProgressIndicatorRole},
       {ui::AX_ROLE_RADIO_BUTTON, NSAccessibilityRadioButtonRole},
       {ui::AX_ROLE_RADIO_GROUP, NSAccessibilityRadioGroupRole},
       {ui::AX_ROLE_REGION, NSAccessibilityGroupRole},
       {ui::AX_ROLE_ROOT_WEB_AREA, @"AXWebArea"},
       {ui::AX_ROLE_ROW, NSAccessibilityRowRole},
       {ui::AX_ROLE_ROW_HEADER, @"AXCell"},
       {ui::AX_ROLE_RULER, NSAccessibilityRulerRole},
       {ui::AX_ROLE_RULER_MARKER, NSAccessibilityRulerMarkerRole},
@@ skipping 203 matching lines @@
   delete this;
 }
 
 gfx::NativeViewAccessible AXPlatformNodeMac::GetNativeViewAccessible() {
   if (!native_node_)
     native_node_.reset([[AXPlatformNodeCocoa alloc] initWithNode:this]);
   return native_node_.get();
 }
 
 }  // namespace ui