This PR focuses on adding type annotations to utility functions,
PropertyDefiner, and its child classes.
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Signed-off-by: Jerens Lensun <jerensslensun@gmail.com>
Signed-off-by: Mukilan Thiyagarajan <mukilan@igalia.com>
Co-authored-by: Mukilan Thiyagarajan <mukilan@igalia.com>