import FIREFOX_52_6_0esr_RELEASE from mozilla-esr52 hg repo

dom/webidl/TreeColumns.webidl

@@ -0,0 +1,54 @@
+/* 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/. */
+
+[Func="IsChromeOrXBL"]
+interface TreeColumns {
+  /**
+   * The tree widget for these columns.
+   */
+  readonly attribute TreeBoxObject? tree;
+
+  /**
+   * The number of columns.
+   */
+  readonly attribute unsigned long count;
+
+  /**
+   * An alias for count (for the benefit of scripts which treat this as an
+   * array).
+   */
+  readonly attribute unsigned long length;
+
+  /**
+   * Get the first/last column.
+   */
+  TreeColumn? getFirstColumn();
+  TreeColumn? getLastColumn();
+
+  /**
+   * Attribute based column getters.
+   */
+  TreeColumn? getPrimaryColumn();
+  TreeColumn? getSortedColumn();
+  TreeColumn? getKeyColumn();
+
+  /**
+   * Get the column for the given element.
+   */
+  TreeColumn? getColumnFor(Element? element);
+
+  /**
+   * Parametric column getters.
+   */
+  getter TreeColumn? getNamedColumn(DOMString name);
+  getter TreeColumn? getColumnAt(unsigned long index);
+
+  /**
+   * This method is called whenever a treecol is added or removed and
+   * the column cache needs to be rebuilt.
+   */
+  void invalidateColumns();
+
+  void restoreNaturalOrder();
+};