Crash when column-sorting while type-ahead filtering

[humdinger]

This is hrev39847.

• Activate type-ahead filtering in Tracker prefs
• Open a folder
• Type a letter to filter the contents
• Click on an attribute column for sorting

--> crash

Thread 2100 caused an exception: Segment violation
[...]
[tcsetpgrp failed in terminal_inferior: Invalid Argument]
[Switching to team /boot/system/Tracker (2076) thread w>home (2100)]
0x003c46d4 in BList::CountItems () from /boot/system/lib/libbe.so
(gdb) bt
#0  0x003c46d4 in BList::CountItems () from /boot/system/lib/libbe.so
#1  0x005430b3 in BObjectList<BPrivate::BTextWidget>::CountItems ()
   from /boot/system/lib/libtracker.so
#2  0x00540965 in BPrivate::BPose::WidgetFor ()
   from /boot/system/lib/libtracker.so
#3  0x00545117 in _ZL20PoseCompareAddWidgetPKN8BPrivate5BPoseES2_PNS_9BPoseViewE () from /boot/system/lib/libtracker.so
#4  0x00563998 in std::merge<BPrivate::BPose**, BPrivate::BPose**, BPrivate::BPose**, PoseComparator> () from /boot/system/lib/libtracker.so
#5  0x00563aaf in std::__merge_sort_loop<BPrivate::BPose**, BPrivate::BPose**, long, PoseComparator> () from /boot/system/lib/libtracker.so
#6  0x00563b16 in std::__merge_sort_with_buffer<BPrivate::BPose**, BPrivate::BPose**, PoseComparator> () from /boot/system/lib/libtracker.so
#7  0x005641e4 in std::__stable_sort_adaptive<BPrivate::BPose**, BPrivate::BPose**, long, PoseComparator> () from /boot/system/lib/libtracker.so
#8  0x00555241 in BPrivate::BPoseView::SortPoses ()
   from /boot/system/lib/libtracker.so
#9  0x00580113 in BPrivate::ColumnDragState::Clicked ()
   from /boot/system/lib/libtracker.so
#10 0x0057ec06 in BPrivate::ColumnTrackState::MouseUp ()
   from /boot/system/lib/libtracker.so
#11 0x0057ec70 in BPrivate::BTitleView::MouseUp ()
   from /boot/system/lib/libtracker.so
#12 0x00374a45 in BWindow::DispatchMessage () from /boot/system/lib/libbe.so
#13 0x00370cad in BWindow::task_looper () from /boot/system/lib/libbe.so
#14 0x002b3cda in BLooper::_task0_ () from /boot/system/lib/libbe.so
#15 0x00607ae4 in thread_entry () from /boot/system/lib/libroot.so
#16 0x78247fec in ?? ()

[humdinger]

(In #7641) Duplicate of #6992.

[stpere]

Fixed in hrev44395, thanks!