Panic on FLOW remainder in UInt to UFix64 conversion

[sisyphusSmiling]

What is the severity of this bug?

Should have:

Reproduction steps

Run a transaction attempting to withdraw an amount of FLOW from a COA that exceeds UFix64 precision which will result in the following error:

error: [Error Code: 1300] evm runtime error: withdraw failed! the balance is susceptible to the rounding error

e.g. the result of running this transaction

This seems to be the result of the check in the impl.newInternalEVMTypeWithdrawFunction() method:

ufix, roundedOff, err := types.ConvertBalanceToUFix64(vault.Balance())
if err != nil {
  panic(err)
}
if roundedOff {
  panic(types.ErrWithdrawBalanceRounding)
}

Expected behaviour

I would expect one of two things:
a. Withdraw the withdrawable amount - e.g. 1000000000012345678 to be withdrawn as 1.0 FLOW
b. The error message to read something like “Withdrawal amounts should be not exceed UFix64 precision”

The former behaviour IMHO is preferable as it allows for the amount to be withdrawn, truncating the remainder without loss.

Screenshots

Example transactions attached

Specifications

• System: N/A
• Go: N/A

Additional context

N/A