public static LightweightTheme OverridePalette(
    LightweightTheme basedOn,
    string name,
    string displayName,
    ResourceDictionary palette
)

Public Shared Function OverridePalette(
    basedOn As LightweightTheme,
    name As String,
    displayName As String,
    palette As ResourceDictionary
) As LightweightTheme