WebKit2 library define a None enum != 0 and fail to compile

[hugopl]

Generating bindings for WebKit2 module you get this error when trying to require the module:

In lib/gi-crystal/src/auto/web_kit2-5.0/web_kit2.cr:503:5

 503 | None          =  2
       ^---
Error: flags enum can't redefine None member to non-0

Crystal language doesn't allow a flag to define None as non-zero, but WebKit2 define this:

  # Flags
  @[Flags]
  enum EditorTypingAttributes : UInt32
    None          =  2
    Bold          =  4
    Italic        =  8
    Underline     = 16
    Strikethrough = 32

    # Returns the type id (GType) registered in GLib type system.
    def self.g_type : UInt64
      LibWebKit2.webkit_editor_typing_attributes_get_type
    end
  end

So, some sort of translation must be done when instances of this type crosses Crystal-C boundary. However what if the C enum is like this:

enum Foo {
  None = 4,
  Troll = 0
};