This is needed by the MemoryFile changes in
https://android-git.corp.google.com/g/2714
where it is used to find out whether a file descriptor
refers to an ashmem region.
The idea here is that some languages need a different form of the month
name in constructions like "January 2" than in "January 2009", since the
one in the "January 2" case really means "of January." So with this change,
a format string of "%-B" will use the standalone month, while "%B" will
continue to use the format month.
