Intl.NumberFormat and Intl.PluralRules don't agree when to call SetNumberFormatDigitOptions

[anba]

• Intl.NumberFormat calls SetNumberFormatDigitOptions after reading "notation", but before reading "compactDisplay".
• Intl.PluralRules calls SetNumberFormatDigitOptions after reading both "notation" and "compactDisplay".

Note: This was explicitly requested in #1019 (comment), but isn't it better to align Intl.NumberFormat and Intl.PluralRules?

[gibson042]

From my perspective, Intl.NumberFormat options interactions are a lost cause until we attempt to address #747, at which point everything can hopefully be brought into alignment. But in the meantime, the other service constructors are not yet in that state and should be treated in accord with where we want to end up.