KRusader crashes when closing krviewer from titlebar
i.e. not from the mainmenu/Krkrusader/quit 
while an html file is open
It doesn't happen with other types of file afaik.


Reproducible: Always

Steps to Reproduce:
1. Open Krusader
2. Select a .html file
3. Press F3 to open the viewer
4. Titlebar/menu on the topleft/Close
Actual Results:  
Crash of both krviewer and krusader

Expected Results:  
krkrusader closes while krusader stays open

Krusader Platform Version 4.8.4 (4.8.4)

Application: Krusader (krusader), signal: Segmentation fault
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
[Current thread is 1 (Thread 0x7f2491506760 (LWP 4728))]

Thread 2 (Thread 0x7f2478267700 (LWP 4729)):
#0  0x00007f248bbf111d in read () at ../sysdeps/unix/syscall-template.S:82
#1  0x00007f2487d6277f in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f2487d271a9 in g_main_context_check () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f2487d275c2 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#4  0x00007f2487d27744 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#5  0x00007f248ca73296 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#6  0x00007f248ca438af in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#7  0x00007f248ca43b38 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#8  0x00007f248c946d70 in QThread::exec() () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#9  0x00007f248ca241bf in ?? () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#10 0x00007f248c949d0b in ?? () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#11 0x00007f2489bf9b50 in start_thread (arg=<optimized out>) at pthread_create.c:304
#12 0x00007f248bbfd0ed in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:112
#13 0x0000000000000000 in ?? ()

Thread 1 (Thread 0x7f2491506760 (LWP 4728)):
[KCrash Handler]
#5  0x00007f248d5072ec in QWidget::window() const () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#6  0x00007f248d4ca104 in QApplicationPrivate::dispatchEnterLeave(QWidget*, QWidget*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#7  0x00007f248d543d16 in QApplication::x11ProcessEvent(_XEvent*) () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#8  0x00007f248d56abc2 in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#9  0x00007f2487d27355 in g_main_context_dispatch () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#10 0x00007f2487d27688 in ?? () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#11 0x00007f2487d27744 in g_main_context_iteration () from /lib/x86_64-linux-gnu/libglib-2.0.so.0
#12 0x00007f248ca73276 in QEventDispatcherGlib::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#13 0x00007f248d56a83e in ?? () from /usr/lib/x86_64-linux-gnu/libQtGui.so.4
#14 0x00007f248ca438af in QEventLoop::processEvents(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#15 0x00007f248ca43b38 in QEventLoop::exec(QFlags<QEventLoop::ProcessEventsFlag>) () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#16 0x00007f248ca48cf8 in QCoreApplication::exec() () from /usr/lib/x86_64-linux-gnu/libQtCore.so.4
#17 0x00000000004501a3 in ?? ()
#18 0x00007f248bb3fead in __libc_start_main (main=<optimized out>, argc=<optimized out>, ubp_av=<optimized out>, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7fff6a76ca18) at libc-start.c:244
#19 0x00000000004525c5 in _start ()