A11y: Add/refactor methods for manipulating bitfields on AXNodeData.

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"
 
 #include "base/bind.h"
 #import "base/mac/mac_util.h"
 #import "base/mac/scoped_nsobject.h"
 #import "base/mac/sdk_forward_declarations.h"
@@ skipping 115 matching lines @@
     : BrowserAccessibilityManager(delegate, factory) {
   Initialize(initial_tree);
 }
 
 BrowserAccessibilityManagerMac::~BrowserAccessibilityManagerMac() {}
 
 // static
 ui::AXTreeUpdate
     BrowserAccessibilityManagerMac::GetEmptyDocument() {
   ui::AXNodeData empty_document;
+  empty_document.ClearBitfields();
   empty_document.id = 0;
   empty_document.role = ui::AX_ROLE_ROOT_WEB_AREA;
   empty_document.state =

[tapted, 2017/05/05 05:53:36]

AddState()?

[Patti Lor, 2017/05/08 00:28:08]

Done.

       1 << ui::AX_STATE_READ_ONLY;
   ui::AXTreeUpdate update;
   update.root_id = empty_document.id;
   update.nodes.push_back(empty_document);
   return update;
 }
 
 BrowserAccessibility* BrowserAccessibilityManagerMac::GetFocus() {
   BrowserAccessibility* focus = BrowserAccessibilityManager::GetFocus();
 
@@ skipping 330 matching lines @@
     NSAccessibilityTextChangeValues : changes,
     NSAccessibilityTextChangeElement : native_node
   };
 }
 
 NSView* BrowserAccessibilityManagerMac::GetParentView() {
   return delegate() ? delegate()->AccessibilityGetAcceleratedWidget() : nullptr;
 }
 
 }  // namespace content