IDL: Use Nullable for union type return value

Source/bindings/scripts/v8_types.py

Index: Source/bindings/scripts/v8_types.py
diff --git a/Source/bindings/scripts/v8_types.py b/Source/bindings/scripts/v8_types.py
index 5d599ab428dddef3676a84cbb6d983f34792fac0..5dab151d8bccca2a249f410b713c68fb42a19aaa 100644
--- a/Source/bindings/scripts/v8_types.py
+++ b/Source/bindings/scripts/v8_types.py
@@ -211,7 +211,14 @@ def cpp_type_initializer(idl_type):
 
 
 def cpp_type_union(idl_type, extended_attributes=None, raw_type=False):
-    return (member_type.cpp_type for member_type in idl_type.member_types)
+    cpp_types = []

[bashi, 2014/08/15 02:43:53]

Use list (not set) to keep the order of members.

+    for member_type in idl_type.member_types:
+        if member_type.is_string_type:
+            cpp_types.append(member_type.cpp_type)
+        else:
+            cpp_types.append(
+                cpp_template_type('Nullable', member_type.cpp_type))
+    return cpp_types
 
 
 def cpp_type_initializer_union(idl_type):
@@ -723,14 +730,20 @@ def v8_set_return_value_union(idl_type, cpp_value, extended_attributes=None, scr
              a sequence (list or tuple) of booleans (if specified individually).
     """
 
-    return [
-        member_type.v8_set_return_value(cpp_value + str(i),
-                                        extended_attributes,
-                                        script_wrappable,
-                                        release and release[i],
-                                        for_main_world)
-            for i, member_type in
-            enumerate(idl_type.member_types)]
+    member_return_values = []
+    for index, member_type in enumerate(idl_type.member_types):
+        if member_type.is_string_type:

[bashi, 2014/08/15 02:43:53]

or cpp_type_has_null_value?

+            member_cpp_value = '%s%d' % (cpp_value, index)
+        else:
+            member_cpp_value = '%s%d.get()' % (cpp_value, index)
+        member_return_values.append(
+            member_type.v8_set_return_value(member_cpp_value,
+                                            extended_attributes,
+                                            script_wrappable,
+                                            release and release[index],
+                                            for_main_world))
+    return member_return_values
+
 
 IdlTypeBase.v8_set_return_value = v8_set_return_value
 IdlUnionType.v8_set_return_value = v8_set_return_value_union