Fix Chrome OS virtual keyboard accessibility

ui/views/accessibility/ax_aura_obj_cache.cc

 // 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.
 
 #include "ui/views/accessibility/ax_aura_obj_cache.h"
 
 #include "base/memory/ptr_util.h"
 #include "base/memory/singleton.h"
 #include "base/strings/string_util.h"
 #include "ui/aura/client/aura_constants.h"
@@ skipping 16 matching lines @@
 AXAuraObjWrapper* AXAuraObjCache::GetOrCreate(View* view) {
   return CreateInternal<AXViewObjWrapper>(view, view_to_id_map_);
 }
 
 AXAuraObjWrapper* AXAuraObjCache::GetOrCreate(Widget* widget) {
   return CreateInternal<AXWidgetObjWrapper>(widget, widget_to_id_map_);
 }
 
 AXAuraObjWrapper* AXAuraObjCache::GetOrCreate(aura::Window* window) {
   if (!focus_client_) {
+    // Note: On Chrome OS, there's exactly one root window per screen,
+    // it's the same as ash::Shell::Get()->GetPrimaryRootWindow() when
+    // there's only one screen. Observing the root window allows us to
+    // detect any time a window is added or removed.
+    //
+    // TODO(dmazzoni): Explicitly observe each root window on Chrome OS
+    // and track as root windows are added and removed.
+    // http://crbug.com/713278
     aura::Window* root_window = window->GetRootWindow();
     if (root_window) {
       focus_client_ = aura::client::GetFocusClient(root_window);
       root_window->AddObserver(this);
       if (focus_client_)
         focus_client_->AddObserver(this);
     }
   }
   return CreateInternal<AXWindowObjWrapper>(window, window_to_id_map_);
 }
@@ skipping 70 matching lines @@
     return GetOrCreate(focused_view);
   return nullptr;
 }
 
 void AXAuraObjCache::OnFocusedViewChanged() {
   View* view = GetFocusedView();
   if (view)
     view->NotifyAccessibilityEvent(ui::AX_EVENT_FOCUS, true);
 }
 
+void AXAuraObjCache::FireEvent(AXAuraObjWrapper* aura_obj,
+                               ui::AXEvent event_type) {
+  if (delegate_)
+    delegate_->OnEvent(aura_obj, event_type);
+}
+
 AXAuraObjCache::AXAuraObjCache()
     : current_id_(1),
       focus_client_(nullptr),
       is_destroying_(false),
       delegate_(nullptr) {}
 
 AXAuraObjCache::~AXAuraObjCache() {
   is_destroying_ = true;
   cache_.clear();
 }
@@ skipping 37 matching lines @@
 
 void AXAuraObjCache::OnWindowFocused(aura::Window* gained_focus,
                                      aura::Window* lost_focus) {
   OnFocusedViewChanged();
 }
 
 void AXAuraObjCache::OnWindowDestroying(aura::Window* window) {
   focus_client_ = nullptr;
 }
 
+void AXAuraObjCache::OnWindowHierarchyChanged(
+    const HierarchyChangeParams& params) {
+  aura::Window* window = params.target;
+  if (window->parent()) {
+    delegate_->OnEvent(GetOrCreate(window->parent()),
+                       ui::AX_EVENT_CHILDREN_CHANGED);
+  }
+}
+
 template <typename AuraViewWrapper, typename AuraView>
 AXAuraObjWrapper* AXAuraObjCache::CreateInternal(
     AuraView* aura_view,
     std::map<AuraView*, int32_t>& aura_view_to_id_map) {
   if (!aura_view)
     return nullptr;
 
   auto it = aura_view_to_id_map.find(aura_view);
 
   if (it != aura_view_to_id_map.end())
@@ skipping 25 matching lines @@
     AuraView* aura_view,
     std::map<AuraView*, int32_t>& aura_view_to_id_map) {
   int32_t id = GetID(aura_view);
   if (id == -1)
     return;
   aura_view_to_id_map.erase(aura_view);
   Remove(id);
 }
 
 }  // namespace views