XCM does withdraw without deposit

[gregdhill]

Describe the bug
The total issuance of the native tokens is slightly off, expected:

• Kintsugi: 10 million KINT (got 9999748)
• Interlay: 1 billion INTR (got 999999989)

To Reproduce

1. Call api.query.tokens.totalIssuance({ Token: "INTR" });
2. Observe that the value is less than the initial distribution
3. Check expected values here

Expected behavior
The total issuance should stay the same.

Additional context
From @sander2:

The culprit for this seems to be xcm: https://polkadot.js.org/apps/?rpc=wss%3A%2F%2Fapi-kusama.interlay.io%2Fparachain#/explorer/query/3364108
It does a withdraw without a deposit

[sander2]

This happens when a user is sending insufficient fees - the BuyExecution instruction fails and execution is aborted without depositing the already-withdrawn tokens. The same behavior is happening on Kusama as well, and I don't think we can easily do something about it. But let's say what parity says about the issue