Update union conversion algorithm

third_party/WebKit/Source/bindings/tests/results/core/LongOrTestDictionary.cpp

Index: third_party/WebKit/Source/bindings/tests/results/core/LongOrTestDictionary.cpp
diff --git a/third_party/WebKit/Source/bindings/tests/results/core/LongOrTestDictionary.cpp b/third_party/WebKit/Source/bindings/tests/results/core/LongOrTestDictionary.cpp
index f0bca72bab76295bb8186127cdf9d693af977ab5..23fc4cf8f4c45b396bcdd8151738c2fa709729d0 100644
--- a/third_party/WebKit/Source/bindings/tests/results/core/LongOrTestDictionary.cpp
+++ b/third_party/WebKit/Source/bindings/tests/results/core/LongOrTestDictionary.cpp
@@ -74,7 +74,16 @@ void V8LongOrTestDictionary::toImpl(v8::Isolate* isolate, v8::Local<v8::Value> v
     if (conversionMode == UnionTypeConversionMode::Nullable && isUndefinedOrNull(v8Value))
         return;
 
-    if (isUndefinedOrNull(v8Value) || (v8Value->IsObject() && !v8Value->IsArray())) {
+    if (isUndefinedOrNull(v8Value)) {
+        TestDictionary cppValue;
+        V8TestDictionary::toImpl(isolate, v8Value, cppValue, exceptionState);
+        if (exceptionState.hadException())
+            return;
+        impl.setTestDictionary(cppValue);
+        return;
+    }
+
+    if (v8Value->IsObject()) {
         TestDictionary cppValue;
         V8TestDictionary::toImpl(isolate, v8Value, cppValue, exceptionState);
         if (exceptionState.hadException())