Avoid race-warning for access to animatableAttributes

third_party/WebKit/Source/core/svg/SVGElement.cpp

Index: third_party/WebKit/Source/core/svg/SVGElement.cpp
diff --git a/third_party/WebKit/Source/core/svg/SVGElement.cpp b/third_party/WebKit/Source/core/svg/SVGElement.cpp
index 5024d320e456a34ab3ac57681c10f25116eb4054..6df1ee97f8c21abcdb686ecd46db9d68db1e5a32 100644
--- a/third_party/WebKit/Source/core/svg/SVGElement.cpp
+++ b/third_party/WebKit/Source/core/svg/SVGElement.cpp
@@ -49,6 +49,7 @@
 #include "core/svg/SVGUseElement.h"
 #include "platform/JSONValues.h"
 #include "wtf/TemporaryChange.h"
+#include "wtf/Threading.h"
 
 namespace blink {
 
@@ -981,7 +982,9 @@ SVGElement::InstanceUpdateBlocker::~InstanceUpdateBlocker()
 #if ENABLE(ASSERT)
 bool SVGElement::isAnimatableAttribute(const QualifiedName& name) const
 {
-    DEFINE_STATIC_LOCAL(HashSet<QualifiedName>, animatableAttributes, ());
+    // This static is atomically initialized to dodge a warning about
+    // a race when dumping debug data for a layer.
+    AtomicallyInitializedStaticReference(HashSet<QualifiedName>, animatableAttributes, new HashSet<QualifiedName>());
 
     if (animatableAttributes.isEmpty()) {
         const QualifiedName* const animatableAttrs[] = {