Fix RPCStateManager Inconsistincy

[scorbajio]

This change fixes a bug in the RPCStateManager that results in an empty account being returned when provider is responding that account does not exist. This should partially address #3301.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 86.90%. Comparing base (a70312d) to head (6a74731).

Additional details and impacted files

Flag	Coverage Δ
block	88.43% <ø> (ø)
blockchain	91.61% <ø> (ø)
client	84.85% <ø> (ø)
common	98.43% <ø> (ø)
devp2p	82.12% <ø> (ø)
ethash	∅ <ø> (∅)
evm	74.16% <ø> (ø)
genesis	99.98% <ø> (ø)
rlp	∅ <ø> (∅)
statemanager	77.08% <100.00%> (+0.07%)	⬆️
trie	89.01% <ø> (-0.32%)	⬇️
tx	95.08% <ø> (ø)
util	89.34% <ø> (ø)
vm	79.87% <ø> (ø)
wallet	88.35% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

[jochem-brouwer]

What about the case if the account is in the state, but it is empty? If you would request the account on the DefaultStateManager it will return the empty account, but the RPC will now return undefined.

We can also decide not to fix this, since these accounts got wiped years back with EIP-158 (I guess I am fine with not fixing this)?

[holgerd77]

Ok, since @jochem-brouwer already expressed being ok with not fully fixing towards the old „empty account“ blocks, I will take this in so it can still make it into todays releases! 🤩