Crash invoking place component tool in eeschema (lp:#1797644)

[Original report](https://bugs.launchpad.net/bugs/1797644) created by **Tomasz Wlostowski (twlostow)**
```
Open any schematic, click on "Add Components" button. Kaboom!

Thread 1 "eeschema" received signal SIGSEGV, Segmentation fault.
std::vector<std::unique_ptr<FOOTPRINT_INFO,
std::default_delete<FOOTPRINT_INFO> >,
std::allocator<std::unique_ptr<FOOTPRINT_INFO,
std::default_delete<FOOTPRINT_INFO> > > >::size (this=0x10)
    at /usr/bin/../lib/gcc/x86_64-linux-
gnu/7.3.0/../../../../include/c++/7.3.0/bits/stl_vector.h:671
671           { return size_type(this->_M_impl._M_finish -
this->_M_impl._M_start); }
(gdb) bt
#0  0x00007fffe38c2dec in std::vector<std::unique_ptr<FOOTPRINT_INFO,
std::default_delete<FOOTPRINT_INFO> >,
std::allocator<std::unique_ptr<FOOTPRINT_INFO,
std::default_delete<FOOTPRINT_INFO> > > >::size() const (this=0x10) at
/usr/bin/../lib/gcc/x86_64-linux-
gnu/7.3.0/../../../../include/c++/7.3.0/bits/stl_vector.h:671
#1  0x00007fffe38c2b39 in FOOTPRINT_LIST::GetCount() const (this=0x0) at
/home/twl/Kicad-dev/kicad-git-master/include/footprint_info.h:217
#2  0x00007fffe38c424a in FOOTPRINT_LIST::GetInstance(KIWAY&) (aKiway=...)
at /home/twl/Kicad-dev/kicad-git-master/common/footprint_info.cpp:141
#3  0x00007fffe3501ce2 in
DIALOG_CHOOSE_COMPONENT::ConstructRightPanel(wxWindow*)
(this=0x7fffffffc270, aParent=0x2b57cd0)
    at /home/twl/Kicad-dev/kicad-git-
master/eeschema/dialogs/dialog_choose_component.cpp:216
#4  0x00007fffe3500f67 in
DIALOG_CHOOSE_COMPONENT::DIALOG_CHOOSE_COMPONENT(SCH_BASE_FRAME*, wxString
const&, wxObjectDataPtr<LIB_TREE_MODEL_ADAPTER>&, int, bool, bool, bool)
(this=0x7fffffffc270, aParent=
    0x17766b0, aTitle=..., aAdapter=..., aDeMorganConvert=1,
aAllowFieldEdits=true, aShowFootprints=true, aAllowBrowser=true)
    at /home/twl/Kicad-dev/kicad-git-
master/eeschema/dialogs/dialog_choose_component.cpp:121
#5  0x00007fffe36a49e2 in
SCH_BASE_FRAME::SelectComponentFromLibTree(SCHLIB_FILTER const*,
std::vector<SCH_BASE_FRAME::COMPONENT_SELECTION,
std::allocator<SCH_BASE_FRAME::COMPONENT_SELECTION> >&, bool, int, int,
bool, LIB_ID const*, bool) (this=0x17766b0, aFilter=0x0,
aHistoryList=std::vector of length 0, capacity 0, aAllowBrowser=true,
aUnit=1, aConvert=1, aShowFootprints=true, aHighlight=0x0,
aAllowFields=true)
    at /home/twl/Kicad-dev/kicad-git-master/eeschema/getpart.cpp:170
#6  0x00007fffe36a5027 in SCH_EDIT_FRAME::Load_Component(SCHLIB_FILTER
const*, std::vector<SCH_BASE_FRAME::COMPONENT_SELECTION,
std::allocator<SCH_BASE_FRAME::COMPONENT_SELECTION> >&, bool) (this=
    0x17766b0, aFilter=0x0, aHistoryList=std::vector of length 0, capacity
0, aAllowBrowser=true) at /home/twl/Kicad-dev/kicad-git-
master/eeschema/getpart.cpp:223
#7  0x00007fffe36e2954 in SCH_EDIT_FRAME::OnLeftClick(wxDC*, wxPoint
const&) (this=0x17766b0, aDC=0x0, aPosition=...) at /home/twl/Kicad-
dev/kicad-git-master/eeschema/onleftclick.cpp:297
#8  0x00007fffe36fd688 in SCH_DRAW_PANEL::OnMouseEvent(wxMouseEvent&)
(this=0x1822ff0, event=...) at /home/twl/Kicad-dev/kicad-git-
master/eeschema/sch_draw_panel.cpp:357
#9  0x00007ffff655e4be in
wxEvtHandler::ProcessEventIfMatchesId(wxEventTableEntryBase const&,
wxEvtHandler*, wxEvent&) () at /usr/lib/x86_64-linux-
gnu/libwx_baseu-3.0.so.0
#10 0x00007ffff655e8ca in wxEvtHandler::SearchDynamicEventTable(wxEvent&)
() at /usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#11 0x00007ffff655e95f in wxEvtHandler::TryHereOnly(wxEvent&) () at
/usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#12 0x00007ffff655ea13 in wxEvtHandler::ProcessEventLocally(wxEvent&) () at
/usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#13 0x00007ffff655ea75 in wxEvtHandler::ProcessEvent(wxEvent&) () at
/usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#14 0x00007ffff655fbe2 in wxEvtHandler::ProcessPendingEvents() () at
/usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#15 0x00007ffff63e09e7 in wxAppConsoleBase::ProcessPendingEvents() () at
/usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#16 0x00007ffff6c8bbbd in wxApp::DoIdle() () at /usr/lib/x86_64-linux-
gnu/libwx_gtk2u_core-3.0.so.0
#17 0x00007ffff6c8bcc3 in  () at /usr/lib/x86_64-linux-
gnu/libwx_gtk2u_core-3.0.so.0
#18 0x00007ffff216b0f5 in g_main_context_dispatch () at
/usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#19 0x00007ffff216b4c0 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#20 0x00007ffff216b7d2 in g_main_loop_run () at /usr/lib/x86_64-linux-
gnu/libglib-2.0.so.0
#21 0x00007ffff3216a37 in gtk_main () at /usr/lib/x86_64-linux-
gnu/libgtk-x11-2.0.so.0
#22 0x00007ffff6cabb05 in wxGUIEventLoop::DoRun() () at
/usr/lib/x86_64-linux-gnu/libwx_gtk2u_core-3.0.so.0
#23 0x00007ffff641aa93 in wxEventLoopBase::Run() () at
/usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#24 0x00007ffff63e20a6 in wxAppConsoleBase::MainLoop() () at
/usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#25 0x000000000042a07f in APP_SINGLE_TOP::OnRun() (this=0x7474b0) at
/home/twl/Kicad-dev/kicad-git-master/common/single_top.cpp:186
#26 0x00007ffff646cae9 in wxEntry(int&, wchar_t**) () at
/usr/lib/x86_64-linux-gnu/libwx_baseu-3.0.so.0
#27 0x00000000004256a6 in main(int, char**) (argc=1, argv=0x7fffffffdb68)
at /home/twl/Kicad-dev/kicad-git-master/common/single_top.cpp:260
```

Story points: 6.0