Improve speech contextual announcements and startCallback synchronization

chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js

Index: chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js
diff --git a/chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js b/chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js
index 7683d4705c6d83a73aa8174ae9af7bf5cf6e251c..bd1684ef0a0a5c3feccb80f4ec461c8dca6a4884 100644
--- a/chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js
+++ b/chrome/browser/resources/chromeos/chromevox/testing/chromevox_next_e2e_test_base.js
@@ -80,5 +80,14 @@ ChromeVoxNextE2ETest.prototype = {
       callback.apply(this, arguments);
     });
     node.addEventListener(eventType, innerCallback, capture);
+  },
+
+  /**
+   * Forces output to place context utterances at the end of output. This eases
+   * rebaselining when changing context ordering for a specific role.
+   */
+  forceContextualLastOutput: function() {
+    for (var role in Output.ROLE_INFO_)
+      Output.ROLE_INFO_[role]['outputContextFirst'] = undefined;
   }
 };