IDL: Values for dictionaries should be a object, null or undefined

Source/bindings/templates/dictionary_v8.cpp

Index: Source/bindings/templates/dictionary_v8.cpp
diff --git a/Source/bindings/templates/dictionary_v8.cpp b/Source/bindings/templates/dictionary_v8.cpp
index 4a18170cb29058d92729815863db2bfd84510c02..c5087b333719489a8959a3384b04820d99199c18 100644
--- a/Source/bindings/templates/dictionary_v8.cpp
+++ b/Source/bindings/templates/dictionary_v8.cpp
@@ -15,6 +15,11 @@ namespace blink {
 
 {{cpp_class}}* {{v8_class}}::toImpl(v8::Isolate* isolate, v8::Handle<v8::Value> v8Value, ExceptionState& exceptionState)
 {
+    if (!isUndefinedOrNull(v8Value) && !v8Value->IsObject()) {
+        // Just returns 0. A TypeError will be thrown later.
+        return 0;
+    }
+
     {{cpp_class}}* impl = {{cpp_class}}::create();
     // FIXME: Do not use Dictionary and DictionaryHelper
     // https://crbug.com/321462