Remember the last key event in wxGTK before passing it over to IM.

Remember the last key event in wxGTK before passing it over to IM.

Save the last key event before calling IM filter to be able to get the correct
modifiers, timestamp, position &c to use for the CHAR event generated from IM
commit callback.

This restores the changes of r34504 which were reverted for unknown (or at
least unmentioned) reason in r34521.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@65517 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775