content: convert accessibility notifications to observer usage

content/browser/renderer_host/render_view_host_impl.cc

Index: content/browser/renderer_host/render_view_host_impl.cc
diff --git a/content/browser/renderer_host/render_view_host_impl.cc b/content/browser/renderer_host/render_view_host_impl.cc
index 3bc3b3c1229819903fb3e30221414f53f3cbb5e0..e13557a3b898d60fc8aad9840d9be5ee03cdd59a 100644
--- a/content/browser/renderer_host/render_view_host_impl.cc
+++ b/content/browser/renderer_host/render_view_host_impl.cc
@@ -175,6 +175,9 @@ RenderViewHostImpl::RenderViewHostImpl(
       has_timed_out_on_unload_(false),
       unload_ack_is_for_cross_site_transition_(false),
       are_javascript_messages_suppressed_(false),
+      accessibility_layout_callback_(base::Bind(&base::DoNothing)),
+      accessibility_load_callback_(base::Bind(&base::DoNothing)),
+      accessibility_other_callback_(base::Bind(&base::DoNothing)),
       sudden_termination_allowed_(false),
       session_storage_namespace_(
           static_cast<SessionStorageNamespaceImpl*>(session_storage)),
@@ -1782,6 +1785,21 @@ void RenderViewHostImpl::UpdateFrameTree(
                                    frame_tree_));
 }
 
+void RenderViewHostImpl::SetAccessibilityLayoutCompleteCallbackForTesting(
+    const base::Closure& callback) {
+  accessibility_layout_callback_ = callback;
+}
+
+void RenderViewHostImpl::SetAccessibilityLoadCompleteCallbackForTesting(
+    const base::Closure& callback) {
+  accessibility_load_callback_ = callback;
+}
+
+void RenderViewHostImpl::SetAccessibilityOtherCallbackForTesting(
+    const base::Closure& callback) {
+  accessibility_other_callback_ = callback;
+}
+
 void RenderViewHostImpl::UpdateWebkitPreferences(
     const webkit_glue::WebPreferences& prefs) {
   Send(new ViewMsg_UpdateWebPreferences(GetRoutingID(), prefs));
@@ -1888,17 +1906,13 @@ void RenderViewHostImpl::OnAccessibilityNotifications(
       accessibility_tree_ = param.acc_tree;
     }
 
-    NotificationType dst_type;
-    if (src_type == AccessibilityNotificationLoadComplete)
-      dst_type = NOTIFICATION_ACCESSIBILITY_LOAD_COMPLETE;
-    else if (src_type == AccessibilityNotificationLayoutComplete)
-      dst_type = NOTIFICATION_ACCESSIBILITY_LAYOUT_COMPLETE;
-    else
-      dst_type = NOTIFICATION_ACCESSIBILITY_OTHER;
-    NotificationService::current()->Notify(
-          dst_type,
-          Source<RenderViewHost>(this),
-          NotificationService::NoDetails());
+    if (src_type == AccessibilityNotificationLayoutComplete) {
+      accessibility_layout_callback_.Run();
+    } else if (src_type == AccessibilityNotificationLoadComplete) {
+      accessibility_load_callback_.Run();
+    } else {
+      accessibility_other_callback_.Run();
+    }
   }
 
   Send(new AccessibilityMsg_Notifications_ACK(GetRoutingID()));