Expose scroll containers via accessibility APIs.

Source/modules/accessibility/AXLayoutObject.cpp

Index: Source/modules/accessibility/AXLayoutObject.cpp
diff --git a/Source/modules/accessibility/AXLayoutObject.cpp b/Source/modules/accessibility/AXLayoutObject.cpp
index 6c92b5afa34e672b004b81c2c2a649bade9cbe72..da5215f2c2cef41e790267b1bd2a27c1f2927399 100644
--- a/Source/modules/accessibility/AXLayoutObject.cpp
+++ b/Source/modules/accessibility/AXLayoutObject.cpp
@@ -244,9 +244,11 @@ bool AXLayoutObject::shouldNotifyActiveDescendant() const
 
 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;
@@ -748,6 +750,9 @@ bool AXLayoutObject::computeAccessibilityIsIgnored(IgnoredReasons* ignoredReason
     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)
@@ -1863,19 +1868,6 @@ void AXLayoutObject::setValue(const String& string)
         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.
 //