Prevent multiple copies of a11y component extensions from opening

AX-Relnotes: n/a.
Bug: None.
Change-Id: I9c1145a4589aa7bbf761c51585055cdb363313d5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2380931Reviewed-by: David Tseng <dtseng@chromium.org>
Commit-Queue: Anastasia Helfinstein <anastasi@google.com>
Cr-Commit-Position: refs/heads/master@{#812441}

chrome/browser/resources/chromeos/accessibility/accessibility_common/BUILD.gn

@@ -87,6 +87,7 @@ js_library("accessibility_common") {
   deps = [
     ":autoclick",
     ":magnifier",
+    "../common:instance_checker",
   ]
   externs_list = [
     "$externs_path/chrome_extensions.js",

chrome/browser/resources/chromeos/accessibility/accessibility_common/accessibility_common_loader.js

@@ -76,5 +76,6 @@ class AccessibilityCommon {
   }
 }
 
+InstanceChecker.closeExtraInstances();
 // Initialize the AccessibilityCommon extension.
 var accessibilityCommon = new AccessibilityCommon();

chrome/browser/resources/chromeos/accessibility/accessibility_common_manifest.json.jinja2

@@ -11,6 +11,8 @@
 {% endif %}
   "background": {
     "scripts": [
+      "common/closure_shim.js",
+      "common/instance_checker.js",
       "accessibility_common/autoclick/autoclick.js",
       "accessibility_common/magnifier/magnifier.js",
       "accessibility_common/accessibility_common_loader.js",

chrome/browser/resources/chromeos/accessibility/chromevox/BUILD.gn

@@ -27,6 +27,7 @@ chromevox_modules = [
   "../common/constants.js",
   "../common/event_generator.js",
   "../common/key_code.js",
+  "../common/instance_checker.js",
   "../common/tree_walker.js",
   "background/annotation/node_identifier.js",
   "background/annotation/user_annotation_handler.js",

chrome/browser/resources/chromeos/accessibility/chromevox/background/background.js

@@ -25,6 +25,7 @@ goog.require('ExtensionBridge');
 goog.require('FindHandler');
 goog.require('FocusAutomationHandler');
 goog.require('GestureCommandHandler');
+goog.require('InstanceChecker');
 goog.require('LiveRegions');
 goog.require('LocaleOutputHelper');
 goog.require('MathHandler');
@@ -555,17 +556,7 @@ Background = class extends ChromeVoxState {
   }
 };
 
-
-// In 'split' manifest mode, the extension system runs two copies of the
-// extension. One in an incognito context; the other not. In guest mode, the
-// extension system runs only the extension in an incognito context. To prevent
-// doubling of this extension, only continue for one context.
-const manifest =
-    /** @type {{incognito: (string|undefined)}} */ (
-        chrome.runtime.getManifest());
-if (manifest.incognito == 'split' && !chrome.extension.inIncognitoContext) {
-  window.close();
-}
+InstanceChecker.closeExtraInstances();
 new Background();
 
 });  // goog.scope

chrome/browser/resources/chromeos/accessibility/common/BUILD.gn

@@ -31,6 +31,7 @@ run_jsbundler("accessibility_common_copied_files") {
     "constants.js",
     "event_generator.js",
     "event_handler.js",
+    "instance_checker.js",
     "key_code.js",
     "rect_util.js",
     "repeated_event_handler.js",
@@ -96,6 +97,10 @@ js_library("event_handler") {
 js_library("key_code") {
 }
 
+js_library("instance_checker") {
+  deps = [ ":closure_shim" ]
+}
+
 js_library("rect_util") {
   externs_list = [ "$externs_path/accessibility_private.js" ]
 }

chrome/browser/resources/chromeos/accessibility/common/instance_checker.js

+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+goog.provide('InstanceChecker');
+
+/**
+ * Used to prevent multiple instances of the extension from running
+ * simultaneously.
+ */
+const InstanceChecker = class {
+  static closeExtraInstances() {
+    // In 'split' manifest mode, the extension system runs two copies of the
+    // extension. One in an incognito context; the other not. In guest mode, the
+    // extension system runs only the extension in an incognito context. To
+    // prevent doubling of this extension, only continue for one context.
+    const manifest =
+        /** @type {{incognito: (string|undefined)}} */ (
+            chrome.runtime.getManifest());
+    if (manifest.incognito == 'split' && !chrome.extension.inIncognitoContext) {
+      window.close();
+    }
+  }
+};

chrome/browser/resources/chromeos/accessibility/select_to_speak/select_to_speak_main.js

@@ -2,4 +2,5 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
+InstanceChecker.closeExtraInstances();
 const selectToSpeak = new SelectToSpeak();

chrome/browser/resources/chromeos/accessibility/select_to_speak_manifest.json.jinja2

@@ -15,6 +15,7 @@
       "common/constants.js",
       "common/key_code.js",
       "common/automation_predicate.js",
+      "common/instance_checker.js",
       "common/rect_util.js",
       "common/tree_walker.js",
       "common/automation_util.js",

chrome/browser/resources/chromeos/accessibility/switch_access/BUILD.gn

@@ -173,7 +173,10 @@ js_library("auto_scan_manager") {
 }
 
 js_library("background") {
-  deps = [ ":switch_access" ]
+  deps = [
+    ":switch_access",
+    "../common:instance_checker",
+  ]
   externs_list = [ "$externs_path/chrome_extensions.js" ]
 }
 

chrome/browser/resources/chromeos/accessibility/switch_access/background.js

@@ -2,14 +2,5 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// In 'split' manifest mode, the extension system runs two copies of the
-// extension. One in an incognito context; the other not. In guest mode, the
-// extension system runs only the extension in an incognito context. To prevent
-// doubling of this extension, only continue for one context.
-const manifest =
-    /** @type {{incognito: (string|undefined)}} */ (
-        chrome.runtime.getManifest());
-if (manifest.incognito == 'split' && !chrome.extension.inIncognitoContext) {
-  window.close();
-}
+InstanceChecker.closeExtraInstances();
 SwitchAccess.initialize();

chrome/browser/resources/chromeos/accessibility/switch_access_manifest.json.jinja2

@@ -19,6 +19,7 @@
       "common/event_generator.js",
       "common/event_handler.js",
       "common/key_code.js",
+      "common/instance_checker.js",
       "common/rect_util.js",
       "common/repeated_event_handler.js",
       "common/repeated_tree_change_handler.js",