Cross-process iframe accessibility.

content/test/accessibility_browser_test_utils.h

 // Copyright 2013 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.
 
 #ifndef CONTENT_TEST_ACCESSIBILITY_BROWSER_TEST_UTILS_H_
 #define CONTENT_TEST_ACCESSIBILITY_BROWSER_TEST_UTILS_H_
 
 #include "base/memory/weak_ptr.h"
 #include "content/common/view_message_enums.h"
 #include "ui/accessibility/ax_node_data.h"
 #include "ui/accessibility/ax_tree.h"
 
 namespace content {
 
 class MessageLoopRunner;
 class RenderViewHostImpl;
 class Shell;
 
 // Create an instance of this class *before* doing any operation that
 // might generate an accessibility event (like a page navigation or
 // clicking on a button). Then call WaitForNotification
 // afterwards to block until the specified accessibility notification has been
 // received.
 class AccessibilityNotificationWaiter {
  public:
-  explicit AccessibilityNotificationWaiter(Shell* shell);
-
   AccessibilityNotificationWaiter(
       Shell* shell,
-      AccessibilityMode accessibility_mode,
-      ui::AXEvent event);
+      AccessibilityMode accessibility_mode = AccessibilityModeOff,
+      ui::AXEvent event = ui::AX_EVENT_NONE,
+      RenderViewHostImpl* render_view_host_impl = NULL);

[ncarter (slow), 2014/05/02 19:10:02]

For some reason, the style guide says you oughta have 2-4 versions of the ctor
here, instead of using default arguments. Because it wouldn't be C++ be without
odious boilerplate, one supposes?
http://google-styleguide.googlecode.com/svn/trunk/cppguide.xml#Default_Arguments

   ~AccessibilityNotificationWaiter();
 
   // Blocks until the specific accessibility notification registered in
   // AccessibilityNotificationWaiter is received. Ignores notifications for
   // "about:blank".
   void WaitForNotification();
 
   // After WaitForNotification has returned, this will retrieve
   // the tree of accessibility nodes received from the renderer process.
   const ui::AXTree& GetAXTree() const;
@@ skipping 11 matching lines @@
   ui::AXEvent event_to_wait_for_;
   scoped_refptr<MessageLoopRunner> loop_runner_;
   base::WeakPtrFactory<AccessibilityNotificationWaiter> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(AccessibilityNotificationWaiter);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_TEST_ACCESSIBILITY_BROWSER_TEST_UTILS_H_