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 b9c2a29355bf436508f266ca991efd854a75c25b..e7096897917d19cd7cc2784293e1ea5865d1d843 100644
--- a/content/browser/renderer_host/render_view_host_impl.cc
+++ b/content/browser/renderer_host/render_view_host_impl.cc
@@ -1795,6 +1795,21 @@ void RenderViewHostImpl::NotifyTimezoneChange() {
   Send(new ViewMsg_TimezoneChange(GetRoutingID()));
 }
 
+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::ClearFocusedNode() {
   Send(new ViewMsg_ClearFocusedNode(GetRoutingID()));
 }
@@ -1892,17 +1907,13 @@ 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()));