fdo#63819 Ctrl+Backspace also deletes the space before the word

Change-Id: I147e8632c36ac0755a539d89ea5d34207839ea7c
Reviewed-on: https://gerrit.libreoffice.org/6518Reviewed-by: Andrzej J.R. Hunt <andrzej@ahunt.org>
Tested-by: Andrzej J.R. Hunt <andrzej@ahunt.org>
Reviewed-by: Björn Michaelsen <bjoern.michaelsen@canonical.com>

sw/source/ui/wrtsh/delete.cxx

@@ -521,8 +521,8 @@ long SwWrtShell::DelPrvWord()
         {
             if ( _PrvWrdForDelete() ) // #i92468#
             {
-                // skip over all-1 spaces
-                short n = -1;
+                // skip over all spaces
+                short n = 0;
                 while( ' ' == GetChar( sal_False, n ))
                     --n;