Description of problem:
vinagre unconditionally calls various commands in its %post and %postun but does not have dependencies them and/or suppress output/error codes from them. This can result in scriptlet errors on package install/erase.

Version-Release number of selected component (if applicable):
vinagre-2.91.91-2.fc15 (rawhide, f15)

How reproducible:
Always

Steps to Reproduce:
1. yum --disablerepo="*" --enablerepo=rawhide --installroot=/home/test/ -y install vinagre
2. rpm -e --root /home/test/ vinagre

(step 2 uses rpm due to a yum bug wrt erasure from chroot)

Actual results:
On step 1:
  Installing : vinagre-2.91.91-2.fc15.x86_64                            189/189 
/var/tmp/rpm-tmp.dOxUFl: line 1: update-desktop-database: command not found
/var/tmp/rpm-tmp.dOxUFl: line 2: gconftool-2: command not found
/var/tmp/rpm-tmp.dOxUFl: line 3: gconftool-2: command not found

On step 2:
/var/tmp/rpm-tmp.I19F16: line 1: update-desktop-database: command not found

Expected results:
No errors/warnings on install and erase.

Additional info:
The calls to update-foo-database calls should be redirected to /dev/null and ||: added to suppress error codes. For gconf schema install, "Requires(post): GConf2" should be added (see http://fedoraproject.org/wiki/Packaging/ScriptletSnippets#GConf for guidelines on handling these)