gettext

b7953995 - xgettext: Simplify code that emits diagnostics with error number.

xgettext: Simplify code that emits diagnostics with error number. * autogen.sh (GNULIB_MODULES_TOOLS_FOR_SRC): Add xstrerror. (GNULIB_MODULES_LIBGETTEXTPO_OTHER): Add strerror_r-posix. * gettext-tools/src/x-csharp.c: Include xstrerror.h. (phase2_getc): Invoke 'xstrerror' and 'if_error' instead of 'error'. * gettext-tools/src/x-javascript.c: Include xstrerror.h. (phase2_getc): Invoke 'xstrerror' and 'if_error' instead of 'error'. * gettext-tools/src/x-python.c: Include xstrerror.h. (phase2_getc): Invoke 'xstrerror' and 'if_error' instead of 'error'.