Fix issue with descendants of aria-activedescendant being marked as focusable.

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

Index: third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp
diff --git a/third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp b/third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp
index 6c1c098d4741d97f4c7fa32b7370b8aac6914c10..379504be0b81b15b4f48ac4a0b992a8830e52770 100644
--- a/third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp
+++ b/third_party/WebKit/Source/modules/accessibility/AXNodeObject.cpp
@@ -1103,8 +1103,8 @@ bool AXNodeObject::canSetFocusAttribute() const
         return true;
 
     // Children of elements with an aria-activedescendant attribute should be
-    // focusable if they have an ARIA role.
-    if (ariaRoleAttribute() != UnknownRole && ancestorExposesActiveDescendant())
+    // focusable if they have a (non-presentational) ARIA role.
+    if (!isPresentational() && ariaRoleAttribute() != UnknownRole && ancestorExposesActiveDescendant())
         return true;
 
     // NOTE: It would be more accurate to ask the document whether setFocusedNode() would