Comment 84 for bug 24689

This causes the printing test from bug 396024 to crash during mochitest.

Part of the stack:
(gdb) bt full
#0 0xffffe410 in __kernel_vsyscall ()
No symbol table info available.
#1 0xb73e8e96 in nanosleep () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.
#2 0xb73e8ca7 in sleep () from /lib/tls/i686/cmov/libc.so.6
No symbol table info available.
#3 0xb7f0ee03 in ah_crap_handler (signum=11) at nsSigHandlers.cpp:149
No locals.
#4 0xb7f23251 in nsProfileLock::FatalSignalHandler (signo=11) at nsProfileLock.cpp:216
        oldact = (sigaction *) 0xb749bff4
#5 <signal handler called>
No symbol table info available.
#6 0xb5b95589 in DocumentViewerImpl::PrintPreview (this=0x8ccb900,
    aPrintSettings=0x8ccc488, aChildDOMWin=0x0, aWebProgressListener=0x8c824d0)
    at /home/reed/mozilla/builds/mozilla/layout/base/nsDocumentViewer.cpp:3537
        rv = <value optimized out>
        xulDoc = {mRawPtr = 0x0}
        docShell = {mRawPtr = 0x0}
        presShell = {mRawPtr = 0x0}
#7 0xb7e0265d in NS_InvokeByIndex_P ()
    at /home/reed/mozilla/builds/mozilla/xpcom/reflect/xptinfo/src/xptiInterfaceInfo.cpp:73
        nsIInterfaceInfo::COMTypeInfo<int>::kIID = {m0 = 559791620, m1 = 38055,
  m2 = 4562, m3 = "�X\000\200_\212]�"}
        nsISupports::COMTypeInfo<int>::kIID = {m0 = 0, m1 = 0, m2 = 0,
  m3 = "�\000\000\000\000\000\000F"}