Expose scroll containers via accessibility APIs.

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 222 matching lines @@
     // We want to notify that the combo box has changed its active descendant,
     // but we do not want to change the focus, because focus should remain with the combo box.
     if (isComboBox())
         return true;
 
     return shouldFocusActiveDescendant();
 }
 
 ScrollableArea* AXLayoutObject::getScrollableAreaIfScrollable() const
 {
-    // If the parent is a FrameView, then this object isn't really scrollable; the parent should handle the scrolling.
+    // FIXME(dmazzoni): the plan is to get rid of AXScrollView, but until
+    // this is done, a WebArea delegates its scrolling to its parent scroll view.
+    // http://crbug.com/484878
     if (parentObject() && parentObject()->isAXScrollView())
-        return 0;
+        return parentObject()->getScrollableAreaIfScrollable();
 
     if (!m_layoutObject || !m_layoutObject->isBox())
         return 0;
 
     LayoutBox* box = toLayoutBox(m_layoutObject);
     if (!box->canBeScrolledAndHasScrollableArea())
         return 0;
 
     return box->scrollableArea();
 }
@@ skipping 481 matching lines @@
         return false;
 
     // Don't ignore generic focusable elements like <div tabindex=0>
     // unless they're completely empty, with no children.
     if (isGenericFocusableElement() && node->hasChildren())
         return false;
 
     if (!ariaAccessibilityDescription().isEmpty())
         return false;
 
+    if (isScrollableContainer())
+        return false;
+
     // By default, objects should be ignored so that the AX hierarchy is not
     // filled with unnecessary items.
     if (ignoredReasons)
         ignoredReasons->append(IgnoredReason(AXUninteresting));
     return true;
 }
 
 //
 // Properties of static elements.
 //
@@ skipping 943 matching lines @@
     if (!m_layoutObject || !m_layoutObject->isBoxModelObject())
         return;
 
     LayoutBoxModelObject* layoutObject = toLayoutBoxModelObject(m_layoutObject);
     if (layoutObject->isTextField() && isHTMLInputElement(*node()))
         toHTMLInputElement(*node()).setValue(string);
     else if (layoutObject->isTextArea() && isHTMLTextAreaElement(*node()))
         toHTMLTextAreaElement(*node()).setValue(string);
 }
 
-// FIXME: This function should use an IntSize to avoid the conversion below.
-void AXLayoutObject::scrollTo(const IntPoint& point) const
-{
-    if (!m_layoutObject || !m_layoutObject->isBox())
-        return;
-
-    LayoutBox* box = toLayoutBox(m_layoutObject);
-    if (!box->canBeScrolledAndHasScrollableArea())
-        return;
-
-    box->scrollToOffset(IntSize(point.x(), point.y()));
-}
-
 //
 // Notifications that this object may have changed.
 //
 
 void AXLayoutObject::handleActiveDescendantChanged()
 {
     Element* element = toElement(layoutObject()->node());
     if (!element)
         return;
     Document& doc = layoutObject()->document();
@@ skipping 604 matching lines @@
         if (label && label->layoutObject()) {
             LayoutRect labelRect = axObjectCache()->getOrCreate(label)->elementRect();
             result.unite(labelRect);
         }
     }
 
     return result;
 }
 
 } // namespace blink