MINIFICPP-1155 - Rocksdb repos print invalid stats

[arpadboda]

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[bakaid]

We should check the return values of the GetProperty calls. When I was first debugging it, it wasn't clear whether it was caused by GetProperty returning false, but us still using the value.

[arpadboda]

We should check the return values of the GetProperty calls. When I was first debugging it, it wasn't clear whether it was caused by GetProperty returning false, but us still using the value.

The strings simply remain empty strings in that case, so we don't have to handle error here, it's a properly designed API :)

[arpadboda]

Added a note to https://issues.apache.org/jira/browse/MINIFICPP-1145 to handle this nicely in the refactor PR.

[bakaid]

@arpadboda Agreed, let's do this once properly in the refactor task.
The fix itself looks good.