As google-im.service in kde-config-telepathy-accounts is identical to the same-named file in account-plugin-google, a possible solution is to dpkg-divert /usr/share/accounts/google-im.service in the preinst of the package.
As google-im.service in kde-config- telepathy- accounts is identical to the same-named file in account- plugin- google, a possible solution is to dpkg-divert /usr/share/ accounts/ google- im.service in the preinst of the package.