Fix Chrome OS virtual keyboard accessibility

chrome/browser/ui/aura/accessibility/automation_manager_aura.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CHROME_BROWSER_UI_AURA_ACCESSIBILITY_AUTOMATION_MANAGER_AURA_H_
 #define CHROME_BROWSER_UI_AURA_ACCESSIBILITY_AUTOMATION_MANAGER_AURA_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 44 matching lines @@
                    views::View* view,
                    ui::AXEvent event_type);
 
   void HandleAlert(content::BrowserContext* context, const std::string& text);
 
   // AXHostDelegate implementation.
   void PerformAction(const ui::AXActionData& data) override;
 
   // views::AXAuraObjCache::Delegate implementation.
   void OnChildWindowRemoved(views::AXAuraObjWrapper* parent) override;
+  void OnEvent(views::AXAuraObjWrapper* aura_obj,
+               ui::AXEvent event_type) override;
 
  protected:
   AutomationManagerAura();
   ~AutomationManagerAura() override;
 
  private:
   friend struct base::DefaultSingletonTraits<AutomationManagerAura>;
 
+  FRIEND_TEST_ALL_PREFIXES(AutomationManagerAuraBrowserTest, WebAppearsOnce);
+
   // Reset state in this manager. If |reset_serializer| is true, reset the
   // serializer to save memory.
   void Reset(bool reset_serializer);
 
   void SendEvent(content::BrowserContext* context,
                  views::AXAuraObjWrapper* aura_obj,
                  ui::AXEvent event_type);
 
   void PerformHitTest(const ui::AXActionData& data);
 
@@ skipping 10 matching lines @@
   std::unique_ptr<AuraAXTreeSerializer> current_tree_serializer_;
 
   bool processing_events_;
 
   std::vector<std::pair<views::AXAuraObjWrapper*, ui::AXEvent>> pending_events_;
 
   DISALLOW_COPY_AND_ASSIGN(AutomationManagerAura);
 };
 
 #endif  // CHROME_BROWSER_UI_AURA_ACCESSIBILITY_AUTOMATION_MANAGER_AURA_H_