extdiff: prevent exception on double-translation
The docstring is translated twice: once when used as a format string,
and once on display. The second translation fails when the first
translation introduces non-ASCII characters in the string.
The problem is that the gettext module calls unicode(message) on the
string, i.e., it decodes it to a Unicode string using the ASCII
encoding (the default encoding). By translating it into a Unicode
string here, the unicode() call becomes a noop.
adding .hgignore
adding a
% invalid eol
applying eol.diff
abort: Unsupported line endings type: LFCR
% force LF
applying eol.diff
'a\nyyyy\ncc\n\nd\ne'
% force CRLF
1 files updated, 0 files merged, 0 files removed, 0 files unresolved
applying eol.diff
'a\r\nyyyy\r\ncc\r\n\r\nd\r\ne'
adding b
% binary patch with --eol
applying bin.diff
'a\x00\nc'