Evm balance mapped with cosmos address return 0x0

[ledanghuy1811]

In process of debug #6, after we run command oraid tx evm set-mapping-evm <pubkey>, the tx mapping evm-cosmos address successfully but when we query evm balance mapped with that cosmos address, the result is 0x0.

[ledanghuy1811]

The error occurs because:

• The flow of query evm balance is that we query the balance of the cosmos address which is mapped with evm address by bank module and denom is EvmDenom (in our case is aorai).
• In file app.go, we instantiate app.evmKeeper with bank keeper param is normal bank keeper (app.bankKeeper)

That why this bank keeper will return balance 0x0.

[ledanghuy1811]

Then we resolve the problem by:

• Make custom bank_keeper (https://github.com/oraichain/ethermint-cosmos-0.50/blob/feat/move-code-from-ethermint/x/evm/keeper/bank_keeper.go). We custom GetBalance method to get actual balance after set mapping evm-cosmos address:

- In `app.go` file, we change instantiate new bank keeper param and repalce it with old bank keeper param when instantiating evmKeeper:

-> Fixed in #2 and ethermint-cosmos-v050