Complete live region support in ChromeVox Next.

chrome/test/data/extensions/api_test/automation/tests/tabs/tree_change.js

Index: chrome/test/data/extensions/api_test/automation/tests/tabs/tree_change.js
diff --git a/chrome/test/data/extensions/api_test/automation/tests/tabs/tree_change.js b/chrome/test/data/extensions/api_test/automation/tests/tabs/tree_change.js
index 19a14168075fdf170c8d8000ec1fd65f2543b78e..cd1272ab618cb1591032e974c4c62736a661da26 100644
--- a/chrome/test/data/extensions/api_test/automation/tests/tabs/tree_change.js
+++ b/chrome/test/data/extensions/api_test/automation/tests/tabs/tree_change.js
@@ -4,6 +4,7 @@
 
 var allTests = [
   function testTreeChangedObserverForCreatingNode() {
+    chrome.automation.setTreeChangeObserverMask("allTreeChanges");
     chrome.automation.addTreeChangeObserver(function(change) {
       if (change.type == "subtreeCreated" && change.target.name == "New") {
         chrome.test.succeed();
@@ -15,6 +16,7 @@ var allTests = [
   },
 
   function testTreeChangedObserverForRemovingNode() {
+    chrome.automation.setTreeChangeObserverMask("allTreeChanges");
     chrome.automation.addTreeChangeObserver(function(change) {
       if (change.type == "nodeRemoved" && change.target.role == "listItem") {
         chrome.test.succeed();
@@ -23,7 +25,24 @@ var allTests = [
 
     var removeButton = rootNode.find({ attributes: { name: 'Remove' }});
     removeButton.doDefault();
+  },
+
+  function testTreeChangedObserverForLiveRegionsOnly() {
+    // This test would fail if we set the mask to allTreeChanges.
+    chrome.automation.setTreeChangeObserverMask('liveRegionTreeChanges');
+    chrome.automation.addTreeChangeObserver(function(change) {
+      if (change.target.name == 'Dead') {
+        chrome.test.fail();
+      }
+      if (change.target.name == 'Live') {
+        chrome.test.succeed();
+      }
+    });
+
+    var liveButton = rootNode.find({ attributes: { name: 'Live' }});
+    liveButton.doDefault();
   }
+
 ];
 
 setUpAndRunTests(allTests, 'tree_change.html');