Fix global enum cast and add Varint::Type cast.

binding_generator.py

@@ -1621,8 +1621,14 @@ def generate_global_constant_binds(api, output_dir):
         if enum_def["name"].startswith("Variant."):
             continue
 
+        if enum_def["is_bitfield"]:
+            header.append(f'VARIANT_BITFIELD_CAST(godot::{enum_def["name"]});')
+        else:
             header.append(f'VARIANT_ENUM_CAST(godot::{enum_def["name"]});')
 
+    # Variant::Type is not a global enum, but only one line, it is worth to place in this file instead of creating new file.
+    header.append(f"VARIANT_ENUM_CAST(godot::Variant::Type);")
+
     header.append("")
 
     header.append(f"#endif // ! {header_guard}")