Fixed Proxy when field/method starts with _
Fixed Proxy when field/method starts with _

If trying to access a JavaScript field/variable that starts with _ (underscore), Dart treats it a library private and member name it suffixed with '@internalLibraryIdentifier' which we have to strip before sending over to the JS side.
a14n/js-interop,a14n/js-interop,dart-archive/js-interop-deprecated