Fix a stack overflow crash in the accessibility code in the renderer. The crash occurs in the

RendererAccessibility::PostAccessibilityNotification function while processing the WebAccessibilityNotificationLayoutComplete 
notification from webkit. This function recursively calls itself with the WebAccessibilityNotificationLayoutComplete
notification leading to infinite recursion.

Fix is to check whether the incoming notification is WebAccessibilityNotificationLayoutComplete before the recursive
call.

BUG=none
TEST=chrome frame tests should pass on the IE6 builder.
Review URL: http://codereview.chromium.org/8952005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@114573 0039d316-1c4b-4281-b951-d872f2087c98

content/renderer/renderer_accessibility.cc

@@ -170,9 +170,11 @@ void RendererAccessibility::PostAccessibilityNotification(
     // TODO(dmazzoni): remove this as soon as
     // https://bugs.webkit.org/show_bug.cgi?id=73460 is fixed.
     last_scroll_offset_ = scroll_offset;
-    PostAccessibilityNotification(
-        document.accessibilityObject(),
-        WebKit::WebAccessibilityNotificationLayoutComplete);
+    if (notification != WebKit::WebAccessibilityNotificationLayoutComplete) {
+      PostAccessibilityNotification(
+          document.accessibilityObject(),
+          WebKit::WebAccessibilityNotificationLayoutComplete);
+    }
   }
 
   // Add the accessibility object to our cache and ensure it's valid.