Bug 1106079 - Avoid highlighter excpetions on XUL windows to break the style-editor; r=past

browser/devtools/styleeditor/StyleEditorUI.jsm

@@ -123,8 +123,15 @@ StyleEditorUI.prototype = {
 
       let hUtils = toolbox.highlighterUtils;
       if (hUtils.hasCustomHighlighter(SELECTOR_HIGHLIGHTER_TYPE)) {
-        this._highlighter =
-          yield hUtils.getHighlighterByType(SELECTOR_HIGHLIGHTER_TYPE);
+        try {
+          this._highlighter =
+            yield hUtils.getHighlighterByType(SELECTOR_HIGHLIGHTER_TYPE);
+        } catch (e) {
+          // The selectorHighlighter can't always be instantiated, for example
+          // it doesn't work with XUL windows (until bug 1094959 gets fixed).
+          console.warn("The selectorHighlighter couldn't be instantiated, " +
+            "elements matching hovered selectors will not be highlighted");
+        }
       }
     }.bind(this)).then(() => {
       this.createUI();

browser/devtools/styleeditor/test/browser.ini

@@ -73,3 +73,4 @@ skip-if = e10s # Bug 1055333 - style editor tests disabled with e10s
 [browser_styleeditor_sourcemap_watching.js]
 skip-if = e10s # Bug 1055333 - style editor tests disabled with e10s
 [browser_styleeditor_transition_rule.js]
+[browser_styleeditor_xul.js]

browser/devtools/styleeditor/test/browser_styleeditor_xul.js

@@ -0,0 +1,20 @@
+/* vim: set ts=2 et sw=2 tw=80: */
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+// Test that the style-editor initializes correctly for XUL windows.
+
+waitForExplicitFinish();
+
+const TEST_URL = "about:config";
+
+let test = asyncTest(function*() {
+  let tab = yield addTab(TEST_URL);
+  let target = TargetFactory.forTab(tab);
+
+  let toolbox = yield gDevTools.showToolbox(target, "styleeditor");
+  let panel = toolbox.getCurrentPanel();
+  yield panel.UI.once("editor-added");
+
+  ok(panel, "The style-editor panel did initialize correctly for the XUL window");
+});