When a small amount of disk space remains to be extended,
the 'Virtual Disk Service' can fail with
VDS_E_EXTENT_SIZE_LESS_THAN_MIN error code.
This happens on environments where a volume has already been extended
and there is a small amount of bytes that somehow remain residual after
the initial extension.
Change-Id: I072ed568ef1f2790e95851b45afb8ffcc0acce0e
f8479e5cbc