This tidies up some logic in the flows that checks registration periods, so that in the create flows we're consistently checking that the requested number of years is <= 10 right away (DomainCreateFlow was deferring it until very late, including after custom logic ran, for no good reason I can see).
It also refactors the validateRegistrationPeriod() overload used by DomainRenewFlow to take the newExpirationTime directly, and just check to ensure that it's >= to now.plusYears(10) (with leap-safety just in case). This is a much simpler check than before, which recomputed the newExpirationTime separately from the logic used by DomainRenewFlow itself (always dangerous) and did a more convoluted and unnecessary comparison involving extendRegistrationWithCap().
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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=151002960
ec4ffe53f0