Make NodeFilter a legacy callback interface.

third_party/WebKit/Source/bindings/tests/idls/core/TestObject.idl

Index: third_party/WebKit/Source/bindings/tests/idls/core/TestObject.idl
diff --git a/third_party/WebKit/Source/bindings/tests/idls/core/TestObject.idl b/third_party/WebKit/Source/bindings/tests/idls/core/TestObject.idl
index f07e4d0472c5b72938e816856559a3c0cb132097..2400fdb041edadb492cc1bed6f442aa2b6f57b19 100644
--- a/third_party/WebKit/Source/bindings/tests/idls/core/TestObject.idl
+++ b/third_party/WebKit/Source/bindings/tests/idls/core/TestObject.idl
@@ -80,7 +80,7 @@ interface TestObject {
     attribute long svgAttribute;
     attribute long xmlAttribute;
     // Non-wrapper types
-    attribute NodeFilter nodeFilterAttribute;
+    readonly attribute NodeFilter nodeFilterAttribute;

[Yuki, 2017/04/27 12:18:29]

If you'd like to test Document.createTreeWalker, you need to make this IDL
operation, not IDL attribute.

If you'd like to test window.NodeFilter, you need ... bashi@?

Anyway, adding |readonly| doesn't make sense to me.

[bashi, 2017/04/27 23:12:32]

If we want to check how we generate bindings for legacy callback interface, we
may want to add a callback interface which contains some const fields in this
directory.

[tkent, 2017/04/28 06:13:37]

The intention was to skip to generate NodeFilter attribute setter because we
don't need to support it. It's not a serious issue, and I reverted this.

Also, I added TestLegacyCallbackInterface.idl and its results.

     attribute SerializedScriptValue serializedScriptValueAttribute;
     attribute any anyAttribute;
     // Custom type conversions