core/state: do not ignore null addr while iterative dump

[pcw109550]

This PR fixes bug which null address is ignored while doing iterative dump.
Null address is excluded in the jsonl result, which makes preimage(null address) not included in the final output.

This PR also adds test for testing iterative dump functionality.

Example

Iterative dump without the fix:

{"root":"0xd5710ea8166b7b04bc2bfb129d7db12931cee82f75ca8e2d075b4884322bf3de"}
{"balance":"22","nonce":0,"root":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","codeHash":"0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470","address":"0x0000000000000000000000000000000000000001","key":"0x1468288056310c82aa4c01a7e12a10f8111a0560e72b700555479031b86c357d"}
{"balance":"1337","nonce":0,"root":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","codeHash":"0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470","key":"0x5380c7b7ae81a58eb98d9c78de4a1fd7fd9535fc953ed2be602daaa41767312a"}
{"balance":"0","nonce":0,"root":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","codeHash":"0x87874902497a5bb968da31a2998d8f22e949d1ef6214bcdedd8bae24cca4b9e3","code":"0x03030303030303","address":"0x0000000000000000000000000000000000000102","key":"0xa17eacbc25cda025e81db9c5c62868822c73ce097cee2a63e33a2e41268358a1"}     
{"balance":"44","nonce":0,"root":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","codeHash":"0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470","address":"0x0000000000000000000000000000000000000002","key":"0xd52688a8f926c816ca1e079067caba944f158e764817b83fc43594370ca9cf62"}

You may observe that address value is not included for null address(third line of jsonl output).

Iterative dump with the fix:

{"root":"0xd5710ea8166b7b04bc2bfb129d7db12931cee82f75ca8e2d075b4884322bf3de"}
{"balance":"22","nonce":0,"root":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","codeHash":"0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470","address":"0x0000000000000000000000000000000000000001","key":"0x1468288056310c82aa4c01a7e12a10f8111a0560e72b700555479031b86c357d"}
{"balance":"1337","nonce":0,"root":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","codeHash":"0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470","address":"0x0000000000000000000000000000000000000000","key":"0x5380c7b7ae81a58eb98d9c78de4a1fd7fd9535fc953ed2be602daaa41767312a"}
{"balance":"0","nonce":0,"root":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","codeHash":"0x87874902497a5bb968da31a2998d8f22e949d1ef6214bcdedd8bae24cca4b9e3","code":"0x03030303030303","address":"0x0000000000000000000000000000000000000102","key":"0xa17eacbc25cda025e81db9c5c62868822c73ce097cee2a63e33a2e41268358a1"}
{"balance":"44","nonce":0,"root":"0x56e81f171bcc55a6ff8345e692c0f86e5b48e01b996cadc001622fb5e363b421","codeHash":"0xc5d2460186f7233c927e7db2dcc703c0e500b653ca82273b7bfad8045d85a470","address":"0x0000000000000000000000000000000000000002","key":"0xd52688a8f926c816ca1e079067caba944f158e764817b83fc43594370ca9cf62"}

[holiman]

This isn't good either, because the addr is not a pointer, so the "we don't have it" null-element is the zero-address.
So as it is on master, it will fail by not showing the 0x000..0 -address in the output. Which is wrong.
In this PR, however, it will fail by showing accounts for which we do not have the preimage (address), as if they were 0x00..00.

[holiman]

Fixed, ptal

[pcw109550]

I understand the fix, but the fix will break t8n: https://github.com/ethereum/go-ethereum/tree/master/cmd/evm:

go-ethereum/cmd/evm/internal/t8ntool/transition.go

Line 303 in 5b792e0

s.DumpToCollector(collector, nil)

[pcw109550]

Fixed to make evmtools happy.

[holiman]

LGTM