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diff --git a/devtools/client/accessibility/provider.js b/devtools/client/accessibility/provider.js
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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/. */
+"use strict";
+
+const {
+  fetchChildren,
+} = require("resource://devtools/client/accessibility/actions/accessibles.js");
+
+/**
+ * Data provider that is responsible for mapping of an accessibles cache to the
+ * data format that is supported by the TreeView component.
+ * @param {Map}      accessibles accessibles object cache
+ * @param {Function} dispatch    react dispatch function that triggers a redux
+ *                               action.
+ */
+
+class Provider {
+  constructor(accessibles, filtered, dispatch) {
+    this.accessibles = accessibles;
+    this.filtered = filtered;
+    this.dispatch = dispatch;
+  }
+
+  /**
+   * Get accessible's cached children if available, if not fetch them from
+   * backend.
+   * @param {Object}  accessible accessible object whose children to get.
+   * @returns {Array} arraof of accessible children.
+   */
+  getChildren(accessible) {
+    if (!accessible || !accessible.actorID || accessible.childCount === 0) {
+      return [];
+    }
+
+    const obj = this.accessibles.get(accessible.actorID);
+    if (!obj || !obj.children) {
+      return this.dispatch(fetchChildren(accessible));
+    }
+
+    return obj.children;
+  }
+
+  /**
+   * Return a flag indicating if an accessible object has any children.
+   * @param {Object}    accessible accessible object whose children to get.
+   * @returns {Boolean} idicator of whether accessible object has children.
+   */
+  hasChildren(accessible) {
+    return accessible.childCount > 0;
+  }
+
+  /**
+   * Get a value for an accessible object. Used to render the second (value)
+   * column of the accessible tree. Corresponds to an accesible object name, if
+   * available.
+   * @param {Object}   accessible accessible object
+   * @returns {String} accessible object value.
+   */
+  getValue(accessible) {
+    return accessible.name || "";
+  }
+
+  /**
+   * Get a label for an accessible object. Used to render the first column of
+   * the accessible tree. Corresponds to an accessible object role.
+   * @param {Object}   accessible accessible object
+   * @returns {String} accessible object label.
+   */
+  getLabel(accessible) {
+    return accessible.role;
+  }
+
+  /**
+   * Get a unique key for an accessible object. Corresponds to an accessible
+   * front's actorID.
+   * @param {Object}   accessible accessible object
+   * @returns {String} a key for an accessible object.
+   */
+  getKey(accessible) {
+    return accessible.actorID;
+  }
+
+  /**
+   * Get a type of an accesible object. Corresponds to the type of an accessible
+   * front.
+   * @param {Object}   accessible accessible object
+   * @returns {String} accessible object type
+   */
+  getType(accessible) {
+    return accessible.typeName;
+  }
+
+  /**
+   * Get the depth of the accesible object in the accessibility tree. When the
+   * tree is filtered it is flattened and the level is set to 0. Otherwise use
+   * internal TreeView level.
+   *
+   * @param {Object}   accessible
+   *                   accessible object
+   * @param {Number}   defaultLevel
+   *                   default level provided by the TreeView component.
+   *
+   * @returns {null|Number}
+   *          depth level of the accessible object.
+   */
+  getLevel(accessible, defaultLevel) {
+    return this.filtered ? 0 : defaultLevel;
+  }
+}
+
+exports.Provider = Provider;