IDL: Generate union type containers

Source/core/animation/AnimationNodeTiming.cpp

Index: Source/core/animation/AnimationNodeTiming.cpp
diff --git a/Source/core/animation/AnimationNodeTiming.cpp b/Source/core/animation/AnimationNodeTiming.cpp
index 9c34d7a49cb84c75eba4ef4a26ba154437e3cae5..20ad3ea99acdb569bed97a3f3178e001bc04b73c 100644
--- a/Source/core/animation/AnimationNodeTiming.cpp
+++ b/Source/core/animation/AnimationNodeTiming.cpp
@@ -5,6 +5,7 @@
 #include "config.h"
 #include "core/animation/AnimationNodeTiming.h"
 
+#include "bindings/core/v8/UnionTypesCore.h"
 #include "core/animation/Animation.h"
 #include "core/animation/AnimationNode.h"
 #include "platform/animation/TimingFunction.h"
@@ -64,16 +65,17 @@ double AnimationNodeTiming::iterations()
 // and bindings/tests/results/V8TestInterface.cpp.
 // FIXME: It might be possible to have 'duration' defined as an attribute in the idl.
 // If possible, fix will be in a follow-up patch.
-void AnimationNodeTiming::getDuration(String propertyName, Nullable<double>& element0, String& element1)
+// http://crbug.com/240176
+void AnimationNodeTiming::getDuration(String propertyName, DoubleOrString& returnValue)
 {
     if (propertyName != "duration")
         return;
 
     if (std::isnan(m_parent->specifiedTiming().iterationDuration)) {
-        element1 = "auto";
+        returnValue.setString("auto");
         return;
     }
-    element0.set(m_parent->specifiedTiming().iterationDuration * 1000);
+    returnValue.setDouble(m_parent->specifiedTiming().iterationDuration * 1000);
     return;
 }