Description of problem:
An attempt to create a disk during VM creation, by clicking on the Create button in the New VM dialog will always fail.

When the user clicks on the OK button the dialog window simply closes, and the New VM dialog is not reshown.

The disk is also not created.

Version-Release number of selected component (if applicable):
3.6.0-0.0.master.20150819133528.gite6b79a7.el6

How reproducible:
100%

Steps to Reproduce:
1. click on the New VM button
2. inside the dialog window click on the Create button, under Instance Images section.
3. Fill the details and click on OK

Actual results:
the dialog simply closes.

Expected results:
The New Virtual Machine dialog must be reshown.

Additional info:
Tried with filling the VM name and without filling the VM name.
It fails in both cases.