New Windows CFTimeZone identifier lookups could be more efficient #5073
Description
In #5070 I restored the Windows behavior for converting between Windows and Olson timezone identifiers. This conversion currently performs a linear search through a list of identifiers to find a matching pair and return the result. We could be more efficient here by pre-sorting the list and performing a binary search or sorting based on a pre-computed hash to mimic a constant-dictionary for constant time lookup.