Merge to M51: Only fire accessible load complete events on the main frame on Android.

content/browser/accessibility/browser_accessibility_manager_android.cc

Index: content/browser/accessibility/browser_accessibility_manager_android.cc
diff --git a/content/browser/accessibility/browser_accessibility_manager_android.cc b/content/browser/accessibility/browser_accessibility_manager_android.cc
index 4d90de4c36dabdeafec6a81d7ac517d40afc6cc9..abfdcf7b55876039a1efe6ad95eac621603c502d 100644
--- a/content/browser/accessibility/browser_accessibility_manager_android.cc
+++ b/content/browser/accessibility/browser_accessibility_manager_android.cc
@@ -214,6 +214,12 @@ void BrowserAccessibilityManagerAndroid::NotifyAccessibilityEvent(
   Java_BrowserAccessibilityManager_handleContentChanged(
       env, obj.obj(), node->unique_id());
 
+  // Ignore load complete events on iframes.
+  if (event_type == ui::AX_EVENT_LOAD_COMPLETE &&
+      node->manager() != GetRootManager()) {
+    return;
+  }
+
   switch (event_type) {
     case ui::AX_EVENT_LOAD_COMPLETE:
       Java_BrowserAccessibilityManager_handlePageLoaded(