Description of problem:
# cibadmin --replace --scope acls --xml-text ""
Aborted (core dumped)

I was just curious if I can remove the <acls/> entry from CIB to return it to the original state, where there is no such element :).

Version-Release number of selected component (if applicable):
pacemaker-cli-1.1.12-6.el6.x86_64

How reproducible:
100%

Steps to Reproduce:
1. cibadmin --replace --scope acls --xml-text ""
2.
3.

Actual results:
core dumped

Expected results:
Error message, non-zero exit code

Additional info:
Core was generated by `cibadmin --replace --scope acls --xml-text '.
Program terminated with signal 6, Aborted.
#0  0x00000033a8032625 in raise (sig=<value optimized out>) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
64	  return INLINE_SYSCALL (tgkill, 3, pid, selftid, sig);
Missing separate debuginfos, use: debuginfo-install audit-libs-2.3.7-5.el6.x86_64 libgcrypt-1.4.5-11.el6_4.x86_64 libgpg-error-1.7-4.el6.x86_64 libtasn1-2.3-6.el6_5.x86_64 nss-softokn-freebl-3.14.3-22.el6_6.x86_64 zlib-1.2.3-29.el6.x86_64
(gdb) bt full
#0  0x00000033a8032625 in raise (sig=<value optimized out>) at ../nptl/sysdeps/unix/sysv/linux/raise.c:64
        resultvar = 0
        pid = 31122
        selftid = 31122
#1  0x00000033a8033e05 in abort () at abort.c:92
        save_stage = 2
        act = {__sigaction_handler = {sa_handler = 0, sa_sigaction = 0}, sa_mask = {__val = {5298259029958695674, 1088, 221967032829, 7468856, 2951, 221967034043, 4205317, 0, 
    221962653021, 206158430216, 140734387012464, 140734387012272, 101680, 7475920, 221967044124, 221967032829}}, sa_flags = 2951, sa_restorer = 0x33ae4426bb}
        sigs = {__val = {32, 0 <repeats 15 times>}}
#2  0x00000033ae414e3c in crm_abort (file=0x33ae4421fd "xml.c", function=<value optimized out>, line=2951, assert_condition=0x33ae4426bb "Cannot parse an empty string", 
    do_core=<value optimized out>, do_fork=<value optimized out>) at utils.c:1177
        rc = 0
        pid = <value optimized out>
        status = 0
        __func__ = "crm_abort"
#3  0x00000033ae420bab in string2xml (input=0x7fff472555f1 "") at xml.c:2951
        xml = 0x0
        output = <value optimized out>
        ctxt = 0x71f4e0
        last_error = 0x71f738
        __func__ = "string2xml"
        __FUNCTION__ = "string2xml"
#4  0x000000000040238e in main (argc=6, argv=0x7fff47254588) at cibadmin.c:394
        argerr = 0
        flag = <value optimized out>
        source = 0x402b05 "input string"
        admin_input_xml = 0x7fff472555f1 ""
        admin_input_file = <value optimized out>
        dangerous_cmd = 0
        admin_input_stdin = 0
        output = 0x0
        input = 0x0
        option_index = 26
        __func__ = "main"
        __FUNCTION__ = "main"