Implement automatic load of composed/embedded automation trees

chrome/renderer/resources/extensions/automation_custom_bindings.js

Index: chrome/renderer/resources/extensions/automation_custom_bindings.js
diff --git a/chrome/renderer/resources/extensions/automation_custom_bindings.js b/chrome/renderer/resources/extensions/automation_custom_bindings.js
index 7a7878dcd1de51510d7e756abb7627c28ff3ec52..f8c9cd24a6c55af5ee7949c363a98f819981240c 100644
--- a/chrome/renderer/resources/extensions/automation_custom_bindings.js
+++ b/chrome/renderer/resources/extensions/automation_custom_bindings.js
@@ -15,21 +15,43 @@ var lastError = require('lastError');
 var logging = requireNative('logging');
 var schema = requireNative('automationInternal').GetSchemaAdditions();
 
+/**
+ * A namespace to export utility functions to other files in automation.
+ */
+window.automationUtil = function() {};
+
 // TODO(aboxhall): Look into using WeakMap
-var idToAutomationRootNode = {};
+automationUtil.idToAutomationRootNode = {};
 var idToCallback = {};
 
-// TODO(dtseng): Move out to automation/automation_util.js or as a static member
-// of AutomationRootNode to keep this file clean.
-/*
+/**
  * Creates an id associated with a particular AutomationRootNode based upon a
  * renderer/renderer host pair's process and routing id.
  */
-var createAutomationRootNodeID = function(pid, rid) {
+automationUtil.createAutomationRootNodeID = function(pid, rid) {
   return pid + '_' + rid;
 };
 
-var DESKTOP_TREE_ID = createAutomationRootNodeID(0, 0);
+automationUtil.DESKTOP_TREE_ID =
+    automationUtil.createAutomationRootNodeID(0, 0);
+
+automationUtil.storeTreeCallback = function(pid, rid, callback) {
+  if (!callback)
+    return;
+
+  var id = automationUtil.createAutomationRootNodeID(pid, rid);
+  var targetTree = automationUtil.idToAutomationRootNode[id];
+  if (!targetTree || !targetTree.loaded) {
+    // If we haven't cached the tree, hold the callback until the tree is
+    // populated by the initial onAccessibilityEvent call.
+    if (id in idToCallback)
+      idToCallback[id].push(callback);
+    else
+      idToCallback[id] = [callback];
+  } else {
+    callback(targetTree);
+  }
+};
 
 automation.registerCustomHook(function(bindingsAPI) {
   var apiFunctions = bindingsAPI.apiFunctions;
@@ -38,45 +60,36 @@ automation.registerCustomHook(function(bindingsAPI) {
   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 idToAutomationRootNode map. The callback to enableTab is 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
+    // a key in the automationUtil.idToAutomationRootNode map. The callback to
+    // enableTab 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.enableTab(tabId, function onEnable(pid, rid) {
       if (lastError.hasError(chrome)) {
         callback();
         return;
       }
-      var id = createAutomationRootNodeID(pid, rid);
-      var targetTree = idToAutomationRootNode[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)
-          idToCallback[id].push(callback);
-        else
-          idToCallback[id] = [callback];
-      } else {
-        callback(targetTree);
-      }
+      automationUtil.storeTreeCallback(pid, rid, callback);
     });
   });
 
   var desktopTree = null;
   apiFunctions.setHandleRequest('getDesktop', function(callback) {
-    desktopTree = idToAutomationRootNode[DESKTOP_TREE_ID];
+    desktopTree =
+        automationUtil.idToAutomationRootNode[automationUtil.DESKTOP_TREE_ID];
     if (!desktopTree) {
-      if (DESKTOP_TREE_ID in idToCallback)
-        idToCallback[DESKTOP_TREE_ID].push(callback);
+      if (automationUtil.DESKTOP_TREE_ID in idToCallback)
+        idToCallback[automationUtil.DESKTOP_TREE_ID].push(callback);
       else
-        idToCallback[DESKTOP_TREE_ID] = [callback];
+        idToCallback[automationUtil.DESKTOP_TREE_ID] = [callback];
 
       // TODO(dtseng): Disable desktop tree once desktop object goes out of
       // scope.
       automationInternal.enableDesktop(function() {
         if (lastError.hasError(chrome)) {
-          delete idToAutomationRootNode[DESKTOP_TREE_ID];
+          delete automationUtil.idToAutomationRootNode[
+              automationUtil.DESKTOP_TREE_ID];
           callback();
           return;
         }
@@ -93,14 +106,14 @@ automation.registerCustomHook(function(bindingsAPI) {
 automationInternal.onAccessibilityEvent.addListener(function(data) {
   var pid = data.processID;
   var rid = data.routingID;
-  var id = createAutomationRootNodeID(pid, rid);
-  var targetTree = idToAutomationRootNode[id];
+  var id = automationUtil.createAutomationRootNodeID(pid, rid);
+  var targetTree = automationUtil.idToAutomationRootNode[id];
   if (!targetTree) {
     // If this is the first time we've gotten data for this tree, it will
     // contain all of the tree's data, so create a new tree which will be
     // bootstrapped from |data|.
     targetTree = new AutomationRootNode(pid, rid);
-    idToAutomationRootNode[id] = targetTree;
+    automationUtil.idToAutomationRootNode[id] = targetTree;
   }
   if (!privates(targetTree).impl.onAccessibilityEvent(data))
     return;
@@ -113,7 +126,7 @@ automationInternal.onAccessibilityEvent.addListener(function(data) {
   // attribute or child nodes. If we've got that, wait for the full tree before
   // calling the callback.
   // TODO(dmazzoni): Don't send down placeholder (crbug.com/397553)
-  if (id != DESKTOP_TREE_ID && !targetTree.attributes.url &&
+  if (id != automationUtil.DESKTOP_TREE_ID && !targetTree.attributes.url &&
       targetTree.children.length == 0) {
     return;
   }
@@ -130,15 +143,15 @@ automationInternal.onAccessibilityEvent.addListener(function(data) {
 });
 
 automationInternal.onAccessibilityTreeDestroyed.addListener(function(pid, rid) {
-  var id = createAutomationRootNodeID(pid, rid);
-  var targetTree = idToAutomationRootNode[id];
+  var id = automationUtil.createAutomationRootNodeID(pid, rid);
+  var targetTree = automationUtil.idToAutomationRootNode[id];
   if (targetTree) {
     privates(targetTree).impl.destroy();
-    delete idToAutomationRootNode[id];
+    delete automationUtil.idToAutomationRootNode[id];
   } else {
     logging.WARNING('no targetTree to destroy');
   }
-  delete idToAutomationRootNode[id];
+  delete automationUtil.idToAutomationRootNode[id];
 });
 
 exports.binding = automation.generate();