Backport SVN commit 728212 by tmcguire:
Backport SVN commit 728212 by tmcguire:

Add saftey check for drag&drop check I introduced.
It did not crash before, but better be safe than sorry.

svn path=/branches/kdepim/enterprise/kdepim/; revision=728451

lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi,lefou/kdepim-noakonadi