Modify the %nonassoc directive in lemon so that it generates a run-time
error rather than a parsing conflict.  This changes is due to a bug report
on the mailing list.  SQLite does not use the %nonassoc directive in its
grammar so this change does not affect SQLite.
Enhance the unix VFS so that it keeps track of the size of unlinked files
internally and thus avoids the need to call fstat() on those files, since
fstat() does not work reliably on unlinked files on some implementations of
FuseFS.
Enhance the unix VFS so that it keeps track of the size of unlinked files
internally and thus avoids the need to call fstat() on those files, since
fstat() does not work reliably on unlinked files on some implementations
of FuseFS.
Avoid an unnecessary initialization of the szFile field of unixFile in
the unix VFS.