Remove all descendant views from AXAuraObjCache when a view is removed.

ui/views/accessibility/ax_aura_obj_cache.h

Index: ui/views/accessibility/ax_aura_obj_cache.h
diff --git a/ui/views/accessibility/ax_aura_obj_cache.h b/ui/views/accessibility/ax_aura_obj_cache.h
index a7bb50c99b42c67e8bc54da21f89fb9f2d3c14a4..1129c1d237a8dde51e796c9bcc57eb4f122db7be 100644
--- a/ui/views/accessibility/ax_aura_obj_cache.h
+++ b/ui/views/accessibility/ax_aura_obj_cache.h
@@ -38,9 +38,9 @@ class VIEWS_EXPORT AXAuraObjCache {
   AXAuraObjWrapper* GetOrCreate(aura::Window* window);
 
   // Gets an id given an Aura view.
-  int32_t GetID(View* view);
-  int32_t GetID(Widget* widget);
-  int32_t GetID(aura::Window* window);
+  int32_t GetID(View* view) const;
+  int32_t GetID(Widget* widget) const;
+  int32_t GetID(aura::Window* window) const;
 
   // Gets the next unique id for this cache. Useful for non-Aura view backed
   // views.
@@ -78,8 +78,9 @@ class VIEWS_EXPORT AXAuraObjCache {
       std::map<AuraView*, int32_t>& aura_view_to_id_map);
 
   template <typename AuraView>
-  int32_t GetIDInternal(AuraView* aura_view,
-                        std::map<AuraView*, int32_t>& aura_view_to_id_map);
+  int32_t GetIDInternal(
+      AuraView* aura_view,
+      const std::map<AuraView*, int32_t>& aura_view_to_id_map) const;
 
   template <typename AuraView>
   void RemoveInternal(AuraView* aura_view,