Trim option names before pre filtering them

[evansolomon]

In get_option() we trim() the option name before looking up its value, but after the pre_option_$option filter runs. I think it makes more sense for the trim() to be done before anything else, and I can't think of a use case for 'foo ' and 'foo' getting different pre_option_$option treatments.

[nacin]

In 22633:

Trim the option name in get_option() before calling the pre_option_$option filter, not after. props evansolomon. fixes #22358.