One accessibility tree per frame.

third_party/WebKit/Source/modules/accessibility/AXLayoutObject.cpp

 /*
 * Copyright (C) 2008 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer.
 * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 1517 matching lines @@
     if (ariaRoleAttribute() == MenuRole) {
         AXObject* parent = menuButtonForMenu();
         if (parent)
             return parent;
     }
 
     LayoutObject* parentObj = layoutParentObject();
     if (parentObj)
         return axObjectCache().getOrCreate(parentObj);
 
-    // A WebArea's parent should be the containing frame (if local) or page popup owner.
+    // A WebArea's parent should be the page popup owner, if any, otherwise null.
     if (isWebArea()) {
         LocalFrame* frame = m_layoutObject->frame();
-        if (frame->owner() && frame->owner()->isLocal()) {
-            HTMLFrameOwnerElement* owner = toHTMLFrameOwnerElement(frame->owner());
-            if (owner && owner->layoutObject())
-                return axObjectCache().getOrCreate(owner->layoutObject());
-        }
         return axObjectCache().getOrCreate(frame->pagePopupOwner());
     }
 
     return 0;
 }
 
 AXObject* AXLayoutObject::computeParentIfExists() const
 {
     if (!m_layoutObject)
         return 0;
 
     if (ariaRoleAttribute() == MenuBarRole)
         return axObjectCache().get(m_layoutObject->parent());
 
     // menuButton and its corresponding menu are DOM siblings, but Accessibility needs them to be parent/child
     if (ariaRoleAttribute() == MenuRole) {
         AXObject* parent = menuButtonForMenu();
         if (parent)
             return parent;
     }
 
     LayoutObject* parentObj = layoutParentObject();
     if (parentObj)
         return axObjectCache().get(parentObj);
 
-    // A WebArea's parent should be the containing frame (if local) or page popup owner.
+    // A WebArea's parent should be the page popup owner, if any, otherwise null.
     if (isWebArea()) {
         LocalFrame* frame = m_layoutObject->frame();
-        if (frame->owner() && frame->owner()->isLocal()) {
-            HTMLFrameOwnerElement* owner = toHTMLFrameOwnerElement(frame->owner());
-            if (owner && owner->layoutObject())
-                return axObjectCache().get(owner->layoutObject());
-        }
         return axObjectCache().get(frame->pagePopupOwner());
     }
 
     return 0;
 }
 
 //
 // Low-level accessibility tree exploration, only for use within the accessibility module.
 //
 
@@ skipping 70 matching lines @@
     computeAriaOwnsChildren(ownedChildren);
 
     for (AXObject* obj = rawFirstChild(); obj; obj = obj->rawNextSibling()) {
         if (!axObjectCache().isAriaOwned(obj)) {
             obj->setParent(this);
             addChild(obj);
         }
     }
 
     addHiddenChildren();
-    addFrameChildren();
     addPopupChildren();
     addImageMapChildren();
     addTextFieldChildren();
     addCanvasChildren();
     addRemoteSVGChildren();
     addInlineTextBoxChildren(false);
 
     for (const auto& child : m_children) {
         if (!child->cachedParentObject())
             child->setParent(this);
@@ skipping 768 matching lines @@
     if (!isHTMLCanvasElement(getNode()))
         return;
 
     // If it's a canvas, it won't have laid out children, but it might have accessible fallback content.
     // Clear m_haveChildren because AXNodeObject::addChildren will expect it to be false.
     ASSERT(!m_children.size());
     m_haveChildren = false;
     AXNodeObject::addChildren();
 }
 
-void AXLayoutObject::addFrameChildren()
-{
-    if (!m_layoutObject || !m_layoutObject->isLayoutPart())
-        return;
-
-    Widget* widget = toLayoutPart(m_layoutObject)->widget();
-    if (!widget || !widget->isFrameView())
-        return;
-
-    Document* doc = toFrameView(widget)->frame().document();
-    if (!doc || !doc->layoutView())
-        return;
-
-    AXObject* axChildFrame = axObjectCache().getOrCreate(doc);
-    if (!axChildFrame->accessibilityIsIgnored())
-        m_children.append(axChildFrame);
-}
-
 void AXLayoutObject::addPopupChildren()
 {
     if (!isHTMLInputElement(getNode()))
         return;
     if (AXObject* axPopup = toHTMLInputElement(getNode())->popupRootAXObject())
         m_children.append(axPopup);
 }
 
 void AXLayoutObject::addRemoteSVGChildren()
 {
@@ skipping 63 matching lines @@
         if (label && label->layoutObject()) {
             LayoutRect labelRect = axObjectCache().getOrCreate(label)->elementRect();
             result.unite(labelRect);
         }
     }
 
     return result;
 }
 
 } // namespace blink