Prepare SVGSMILElement for oilpan

Source/core/svg/animation/SVGSMILElement.cpp

Index: Source/core/svg/animation/SVGSMILElement.cpp
diff --git a/Source/core/svg/animation/SVGSMILElement.cpp b/Source/core/svg/animation/SVGSMILElement.cpp
index 54f5c5a45a9113cbbe931808d0aca72a20846060..3a914e8d23c01755a6d61dc60287753ed5350176 100644
--- a/Source/core/svg/animation/SVGSMILElement.cpp
+++ b/Source/core/svg/animation/SVGSMILElement.cpp
@@ -205,7 +205,6 @@ SVGSMILElement::~SVGSMILElement()
     smilRepeatEventSender().cancelEvent(this);
     smilRepeatNEventSender().cancelEvent(this);
 #if !ENABLE(OILPAN)
-    // FIXME: Oilpan: Clear |m_syncBaseDependents| using weak processing.
     clearConditions();
 
     if (m_timeContainer && m_targetElement && hasValidAttributeName())
@@ -602,12 +601,14 @@ void SVGSMILElement::connectSyncBaseConditions()
         Condition* condition = m_conditions[n].get();
         if (condition->type() == Condition::Syncbase) {
             ASSERT(!condition->baseID().isEmpty());
-            condition->setSyncBase(treeScope().getElementById(AtomicString(condition->baseID())));
-            if (!condition->syncBase() || !isSVGSMILElement(*condition->syncBase())) {
+            Element* element = treeScope().getElementById(AtomicString(condition->baseID()));
+            if (!element || !isSVGSMILElement(*element)) {
                 condition->setSyncBase(0);
                 continue;
             }
-            toSVGSMILElement(condition->syncBase())->addSyncBaseDependent(this);
+            SVGSMILElement* svgSMILElement = toSVGSMILElement(element);
+            condition->setSyncBase(svgSMILElement);
+            svgSMILElement->addSyncBaseDependent(this);
         }
     }
 }
@@ -621,7 +622,7 @@ void SVGSMILElement::disconnectSyncBaseConditions()
         Condition* condition = m_conditions[n].get();
         if (condition->type() == Condition::Syncbase) {
             if (condition->syncBase())
-                toSVGSMILElement(condition->syncBase())->removeSyncBaseDependent(this);
+                condition->syncBase()->removeSyncBaseDependent(this);
             condition->setSyncBase(0);
         }
     }
@@ -1246,8 +1247,8 @@ bool SVGSMILElement::progress(SMILTime elapsed, SVGSMILElement* resultElement, b
 void SVGSMILElement::notifyDependentsIntervalChanged()
 {
     ASSERT(m_intervalBegin.isFinite());
-    DEFINE_STATIC_LOCAL(HashSet<SVGSMILElement*>, loopBreaker, ());
-    if (!loopBreaker.add(this).isNewEntry)
+    DEFINE_STATIC_LOCAL(OwnPtrWillBePersistent<WillBeHeapHashSet<RawPtrWillBeMember<SVGSMILElement> > >, loopBreaker, (adoptPtrWillBeNoop(new WillBeHeapHashSet<RawPtrWillBeMember<SVGSMILElement> >())));

[haraken, 2014/05/29 08:11:52]

Discussed offline. I wonder if this Persistent<Member> might cause leaks, but it
won't happen because the entry is removed when we finish the recursion of
notifyDependentsIntervalChanged.

Would you add a comment about why we need the loopBreaker hack?

+    if (!loopBreaker->add(this).isNewEntry)
         return;
 
     TimeDependentSet::iterator end = m_syncBaseDependents.end();
@@ -1256,7 +1257,7 @@ void SVGSMILElement::notifyDependentsIntervalChanged()
         dependent->createInstanceTimesFromSyncbase(this);
     }
 
-    loopBreaker.remove(this);
+    loopBreaker->remove(this);
 }
 
 void SVGSMILElement::createInstanceTimesFromSyncbase(SVGSMILElement* syncBase)