Add null check to AXLayoutObject::computeAccessibilityIsIgnored

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 526 matching lines @@
 
     return AXObject::defaultObjectInclusion(ignoredReasons);
 }
 
 bool AXLayoutObject::computeAccessibilityIsIgnored(IgnoredReasons* ignoredReasons) const
 {
 #if ENABLE(ASSERT)
     ASSERT(m_initialized);
 #endif
 
+    if (!m_layoutObject)
+        return true;
+
     // Check first if any of the common reasons cause this element to be ignored.
     // Then process other use cases that need to be applied to all the various roles
     // that AXLayoutObjects take on.
     AXObjectInclusion decision = defaultObjectInclusion(ignoredReasons);
     if (decision == IncludeObject)
         return false;
     if (decision == IgnoreObject)
         return true;
 
     // If this element is within a parent that cannot have children, it should not be exposed
@@ skipping 1998 matching lines @@
         if (label && label->layoutObject()) {
             LayoutRect labelRect = axObjectCache().getOrCreate(label)->elementRect();
             result.unite(labelRect);
         }
     }
 
     return result;
 }
 
 } // namespace blink