Cross-process iframe accessibility.

content/test/accessibility_browser_test_utils.h

Index: content/test/accessibility_browser_test_utils.h
diff --git a/content/test/accessibility_browser_test_utils.h b/content/test/accessibility_browser_test_utils.h
index 4cffa08435a0d2ce8b120c310daec511445e2b92..e59d829406b566b1e20175042279cdad45bf84b3 100644
--- a/content/test/accessibility_browser_test_utils.h
+++ b/content/test/accessibility_browser_test_utils.h
@@ -23,12 +23,11 @@ class Shell;
 // 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