LCL: New method ForceFilter for FilterEdit. Issue #25258, patch from Cyrax.

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@43482 4005530d-fff6-0310-9dd1-cebe43e6787f
Clear the filter edit when leaving package editor. Issue #25258, patch from Cyrax.

git-svn-id: http://svn.freepascal.org/svn/lazarus/trunk@43483 4005530d-fff6-0310-9dd1-cebe43e6787f