Incorrect VDI depth and total VDI to coalesce count in SR advanced view

[olivierlambert]

On XOA latest, when creating 20 VMs from the same template, each new VM disk will have the VM disk template as parent (normal).

When you snapshot those VMs and then removing those VMs, we have an incorrect count on the depth and therefore VDI to coalesce.

Here is an example, before removing the snaps: https://paste.vates.tech/?945a3d4691ddf4f8#6GNREJhFBBbqEqXd995GTy2DicJspyngES7gSHLZV2YE

When removing the snapshots: https://paste.vates.tech/?a91210f37ddd5b89#BrVuqJLRF7BqPGKhzabf3AJUY2M9vjp533b2VhG2Bx1b

At this point, XO is reporting 201 VDIs to coalesce:

Which is wrong. Also, we can see that some VDIs are counted with a depth of 18, which is not true either. I think the total count is doing a sum of the depth of each VDI, giving this wrong total number of VDI to coalesce.