logIndex broken on v3.0.0-alpha7

[mriccobene]

In the RPC Integration test suite, the following tests fail on the v3.0.0-alpha7:

• eth_getLogs/test_16.tar
• eth_getLogs/test_17.json
• eth_getLogs/test_18.json
• eth_getLogs/test_19.tar
• eth_getLogs/test_20.json

It seems that more log objects inserted in a certain block have a coincident log index while before it was not so.

This is the diff between the expected response and the actual response of the eth_getLogs in the test 17:

Also, if you request all logs of a specific block then log indexes seem broken on alpha7.
This request:

curl \
  -X POST \
  -H "Content-Type: application/json" \
  --data '{
    "id": 1,
    "jsonrpc": "2.0",
    "method": "eth_getLogs",
    "params": [
      {
        "address": [],
        "fromBlock": "0x3D08F6",
        "toBlock": "0x3D08F6",
        "topics": [[]]
      }
    ]
  }' \
  http://localhost:8545

produces different responses on alpha5 and alpha7: the only difference is in the logIndex.
On alpha5 logIndex is progressing from 0x0 to 0x23 but on alpha7 it is always 0x1a or 0x1b.
Here the responses:
alpha5.json
alpha7.json

Note that the problem does not seem to be related to eth_getLogs but to the code that writes the logIndex to snapshots/database, because if we run erigon alpha7 with an alpha5 db then the answers are ok.