SVG animate element's begin/end attribute set by js, should animate.

Source/core/svg/animation/SVGSMILElement.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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 539 matching lines @@
         m_cachedMax = invalidCachedTime;
     else if (attrName == SVGNames::attributeNameAttr)
         setAttributeName(constructQualifiedName(this, fastGetAttribute(SVGNames::attributeNameAttr)));
     else if (attrName.matches(XLinkNames::hrefAttr)) {
         SVGElement::InvalidationGuard invalidationGuard(this);
         buildPendingResource();
         if (m_targetElement)
             clearAnimatedType();
     } else if (attrName == SVGNames::beginAttr || attrName == SVGNames::endAttr) {
         if (inDocument()) {
+            connectEventBaseConditions();
             if (attrName == SVGNames::beginAttr)
                 beginListChanged(elapsed());
             else if (attrName == SVGNames::endAttr)
                 endListChanged(elapsed());
         }
     } else {
         SVGElement::svgAttributeChanged(attrName);
         return;
     }
 
@@ skipping 783 matching lines @@
     visitor->trace(m_targetElement);
     visitor->trace(m_timeContainer);
     visitor->trace(m_conditions);
     visitor->trace(m_syncBaseDependents);
 #endif
     SVGElement::trace(visitor);
     SVGTests::trace(visitor);
 }
 
 } // namespace blink