Allow requesting Automation tree by tabId

chrome/renderer/resources/extensions/automation_custom_bindings.js

 // Copyright 2014 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.
 
 // Custom bindings for the automation API.
 var AutomationNode = require('automationNode').AutomationNode;
 var AutomationTree = require('automationTree').AutomationTree;
 var automation = require('binding').Binding.create('automation');
 var automationInternal =
     require('binding').Binding.create('automationInternal').generate();
@@ skipping 17 matching lines @@
 var createAutomationTreeID = function(pid, rid) {
   return pid + '_' + rid;
 };
 
 var DESKTOP_TREE_ID = createAutomationTreeID(0, 0);
 
 automation.registerCustomHook(function(bindingsAPI) {
   var apiFunctions = bindingsAPI.apiFunctions;
 
   // TODO(aboxhall, dtseng): Make this return the speced AutomationRootNode obj.
-  apiFunctions.setHandleRequest('getTree', function(callback) {
-    // enableCurrentTab() ensures the renderer for the current tab has
+  apiFunctions.setHandleRequest('getTree', function getTree(tabId, callback) {
+    // enableTab() ensures the renderer for the active or specified tab has
     // accessibility enabled, and fetches its process and routing ids to use as
-    // a key in the idToAutomationTree map. The callback to enableCurrentTab is
+    // a key in the idToAutomationTree map. The callback to enableActiveTab is
     // bound to the callback passed in to getTree(), so that once the tree is
     // available (either due to having been cached earlier, or after an
     // accessibility event occurs which causes the tree to be populated), the
     // callback can be called.
-    automationInternal.enableCurrentTab(function(pid, rid) {
+    automationInternal.enableTab(tabId, function onEnable(pid, rid) {
       if (lastError.hasError(chrome)) {
         callback();
         return;
       }
       var id = createAutomationTreeID(pid, rid);
       var targetTree = idToAutomationTree[id];
       if (!targetTree) {
         // If we haven't cached the tree, hold the callback until the tree is
         // populated by the initial onAccessibilityEvent call.
         if (id in idToCallback)
@@ skipping 62 matching lines @@
 });
 
 exports.binding = automation.generate();
 
 // Add additional accessibility bindings not specified in the automation IDL.
 // Accessibility and automation share some APIs (see
 // ui/accessibility/ax_enums.idl).
 forEach(schema, function(k, v) {
   exports.binding[k] = v;
 });