Bug 1596918: Part 1c - Make some more globals available to SpecialPowers.spawn tasks. r=mccr8

A number of additional globals are available to ContentTask.spawn tasks
compared to SpecialPowers.spawn tasks. Most of these are available by
accident, as a side-effect of running in a shared frame script global, or
being evaled in the context of the content-task.js frame script, but several
of them are pretty broadly useful, or difficult to obtain from a Sandbox
environment without reaching into arbitrary nearby globals.

This patch adds some of the more useful ones to the default task environment.

Differential Revision: https://phabricator.services.mozilla.com/D53736

--HG--
extra : moz-landing-system : lando

testing/specialpowers/content/SpecialPowersChild.jsm

@@ -1709,12 +1709,17 @@ class SpecialPowersChild extends JSWindowActorChild {
 
     sb.sandbox.SpecialPowers = this;
     sb.sandbox.ContentTaskUtils = ContentTaskUtils;
-    Object.defineProperty(sb.sandbox, "content", {
+    for (let [global, prop] of Object.entries({
+      content: "contentWindow",
+      docShell: "docShell",
+    })) {
+      Object.defineProperty(sb.sandbox, global, {
         get: () => {
-        return this.contentWindow;
+          return this[prop];
         },
         enumerable: true,
       });
+    }
 
     return sb.execute(task, args, caller);
   }

testing/specialpowers/content/SpecialPowersEventUtils.jsm

@@ -0,0 +1,42 @@
+/* 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";
+
+var EXPORTED_SYMBOLS = ["EventUtils"];
+
+/**
+ * Loads a stub copy of EventUtils.js which can be used by things like
+ * content tasks without holding any direct references to windows.
+ */
+
+const { Services } = ChromeUtils.import("resource://gre/modules/Services.jsm");
+
+let EventUtils = {};
+
+EventUtils.window = {};
+EventUtils.parent = EventUtils.window;
+EventUtils._EU_Ci = Ci;
+EventUtils._EU_Cc = Cc;
+
+EventUtils.synthesizeClick = element =>
+  new Promise(resolve => {
+    element.addEventListener("click", () => resolve(), { once: true });
+
+    EventUtils.synthesizeMouseAtCenter(
+      element,
+      { type: "mousedown", isSynthesized: false },
+      element.ownerGlobal
+    );
+    EventUtils.synthesizeMouseAtCenter(
+      element,
+      { type: "mouseup", isSynthesized: false },
+      element.ownerGlobal
+    );
+  });
+
+Services.scriptloader.loadSubScript(
+  "chrome://mochikit/content/tests/SimpleTest/EventUtils.js",
+  EventUtils
+);

testing/specialpowers/content/SpecialPowersSandbox.jsm

@@ -18,6 +18,14 @@ ChromeUtils.defineModuleGetter(
   "resource://testing-common/Assert.jsm"
 );
 
+const SANDBOX_GLOBALS = [
+  "Blob",
+  "ChromeUtils",
+  "TextDecoder",
+  "TextEncoder",
+  "URL",
+];
+
 let expectFail = false;
 function expectingFail(fn) {
   try {
@@ -38,7 +46,7 @@ class SpecialPowersSandbox {
     this.sandbox = Cu.Sandbox(
       Cu.getGlobalForObject({}),
       Object.assign(
-        { wantGlobalProperties: ["ChromeUtils"] },
+        { wantGlobalProperties: SANDBOX_GLOBALS },
         opts.sandboxOptions
       )
     );
@@ -53,11 +61,18 @@ class SpecialPowersSandbox {
       });
     }
 
-    for (let [symbol, url] of Object.entries(opts.imports || {})) {
+    let imports = {
+      EventUtils: "resource://specialpowers/SpecialPowersEventUtils.jsm",
+      Services: "resource://gre/modules/Services.jsm",
+      ...opts.imports,
+    };
+    for (let [symbol, url] of Object.entries(imports)) {
       ChromeUtils.defineModuleGetter(this.sandbox, symbol, url);
     }
 
     Object.assign(this.sandbox, {
+      BrowsingContext,
+      InspectorUtils,
       ok: (...args) => {
         this.Assert.ok(...args);
       },

testing/specialpowers/moz.build

@@ -20,6 +20,7 @@ FINAL_TARGET_FILES.content += [
     'content/MockFilePicker.jsm',
     'content/MockPermissionPrompt.jsm',
     'content/SpecialPowersChild.jsm',
+    'content/SpecialPowersEventUtils.jsm',
     'content/SpecialPowersParent.jsm',
     'content/SpecialPowersSandbox.jsm',
     'content/WrapPrivileged.jsm',