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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
/* eslint-env mozilla/frame-script */
(function () {
let gAccService = 0;
function initAccessibility() {
if (!gAccService) {
var service = Cc["@mozilla.org/accessibilityService;1"];
if (service) {
// fails if build lacks accessibility module
gAccService = Cc["@mozilla.org/accessibilityService;1"].getService(
Ci.nsIAccessibilityService
);
}
}
return !!gAccService;
}
function getAccessible(aNode) {
try {
return gAccService.getAccessibleFor(aNode);
} catch (e) {}
return null;
}
function ensureAccessibleTreeForNode(aNode) {
var acc = getAccessible(aNode);
ensureAccessibleTreeForAccessible(acc);
}
function ensureAccessibleTreeForAccessible(aAccessible) {
var child = aAccessible.firstChild;
while (child) {
ensureAccessibleTreeForAccessible(child);
try {
child = child.nextSibling;
} catch (e) {
child = null;
}
}
}
// Walk accessible tree of the given identifier to ensure tree creation
function ensureAccessibleTreeForId(aID) {
var node = content.document.getElementById(aID);
if (!node) {
return;
}
ensureAccessibleTreeForNode(node);
}
addEventListener("DOMContentLoaded", () => {
Cu.exportFunction(initAccessibility, content, {
defineAs: "initAccessibility",
});
Cu.exportFunction(ensureAccessibleTreeForId, content, {
defineAs: "ensureAccessibleTreeForId",
});
});
})();