Account tx types in estimateGas

[2dvorak]

For fee delegated tx, user signs the tx including the gas limit. If the user has no balance, the user cannot properly estimate required gas, because the estimateGas API would return error (i.e., "insufficient funds .."). So the user has to arbitrarily pick a number for gas limit, or call estimateGas using another account with enough balance as from.

We should consider such cases (i.e., other types of tx) in estimateGas.

• Allow zero-balance account to estimate gas for fee delegated tx

[exalate-issue-sync]

Exalate commented: Issue Created by: 2dvorak