[SDK audit] Recommendation: Don’t silently treat null Double? values as 0.0

[HonzaR]

Is your feature request related to a problem? Please describe.

The following code from CurrencyFormatter.kt, used to convert a Double? value to a BigDecimal
silently converts the value null to 0.0.

Describe the solution you'd like

The value null could indicate that some error occurred in acquiring the value being converted, and so it would be safer to throw an exception in the null case, rather than assume null represents the value 0.0.
The same pattern exists in several other functions in CurrencyFormatter.kt.

Alternatives you've considered

Additional context