Introduce toSVGSMILElement, and use it

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 518 matching lines @@
             ASSERT(!condition.m_eventListener);
             condition.m_eventListener = ConditionEventListener::create(this, &condition);
             eventBase->addEventListener(condition.m_name, condition.m_eventListener, false);
         } else if (condition.m_type == Condition::Syncbase) {
             ASSERT(!condition.m_baseID.isEmpty());
             condition.m_syncbase = treeScope()->getElementById(condition.m_baseID);
             if (!isSMILElement(condition.m_syncbase.get())) {
                 condition.m_syncbase = 0;
                 continue;
             }
-            SVGSMILElement* syncbase = static_cast<SVGSMILElement*>(condition.m_syncbase.get());
+            SVGSMILElement* syncbase = toSVGSMILElement(condition.m_syncbase.get());

[tkent, 2013/07/24 05:19:26]

We can remove the local variable |syncbase|.

             syncbase->addTimeDependent(this);
         }
     }
 }
 
 void SVGSMILElement::disconnectConditions()
 {
     if (!m_conditionsConnected)
         return;
     m_conditionsConnected = false;
     for (unsigned n = 0; n < m_conditions.size(); ++n) {
         Condition& condition = m_conditions[n];
         if (condition.m_type == Condition::EventBase) {
             ASSERT(!condition.m_syncbase);
             if (!condition.m_eventListener)
                 continue;
             // Note: It's a memory optimization to try to remove our condition
             // event listener, but it's not guaranteed to work, since we have
             // no guarantee that eventBaseFor() will be able to find our condition's
             // original eventBase. So, we also have to disconnect ourselves from
             // our condition event listener, in case it later fires.
             Element* eventBase = eventBaseFor(condition);
             if (eventBase)
                 eventBase->removeEventListener(condition.m_name, condition.m_eventListener.get(), false);
             condition.m_eventListener->disconnectAnimation();
             condition.m_eventListener = 0;
         } else if (condition.m_type == Condition::Syncbase) {
             if (condition.m_syncbase) {
                 ASSERT(isSMILElement(condition.m_syncbase.get()));

[tkent, 2013/07/24 05:19:26]

This assertion is redundant.  toSVgSMILElement() covers it.

-                static_cast<SVGSMILElement*>(condition.m_syncbase.get())->removeTimeDependent(this);
+                toSVGSMILElement(condition.m_syncbase.get())->removeTimeDependent(this);
             }
         }
         condition.m_syncbase = 0;
     }
 }
 
 void SVGSMILElement::setAttributeName(const QualifiedName& attributeName)
 {
     if (m_timeContainer && m_targetElement && m_attributeName != attributeName) {
         if (hasValidAttributeName())
@@ skipping 608 matching lines @@
     addBeginTime(elapsed, elapsed);
 }
 
 void SVGSMILElement::endedActiveInterval()
 {
     clearTimesWithDynamicOrigins(m_beginTimes);
     clearTimesWithDynamicOrigins(m_endTimes);
 }
 
 }