Fix emitting events via module member access

[rodiazet]

This PR fixes a bug in implementation of accessing an event which is defined in a separated, imported contract.

Closes: #16314

[cameel]

There is a related error message in the parser that is missing events as well:

solidity/libsolidity/parsing/Parser.cpp

Line 173 in 2f5d103

fatalParserError(7858_error, "Expected pragma, import directive or contract/interface/library/struct/enum/constant/function/error definition.");

It should also mention UDVTs, but I'd recommend just replacing "struct/enum" with a catch-all "user-defined type" instead.

[cameel]

For more complete coverage, we should add other types of tests here:

• natspecJSON
• ABIJSON
• ASTJSON (to make sure it appears in listed in usedEvents)

And I suspect we're missing this coverage for imported errors as well.

[cameel]

BTW, I think ABI/AST tests are not multi-file but you can work around it by just having the file import itself as a module.

[cameel]

No contract is being imported here. event_emit_from_module_via_member_access.sol would be a more accurate name.

[cameel]

A bit clearer naming so that it's more obvious at a glance what is a file, what is a module, etc.

Suggested change

	==== Source: a ====
	event Transfer(address indexed _from, address indexed _to, uint256 _value);
	==== Source: b ====
	import * as Test2 from "a";
	==== Source: A.sol ====
	event Transfer(address indexed _from, address indexed _to, uint256 _value);
	==== Source: B.sol ====
	import * as M from "A.sol";

[cameel]

Do we have coverage for the M.C.Transfer and M1.M2.Transfer cases (where C is a contract)?

And same for errors?

[cameel]

event which is defined in a separated, imported contract.

Note that this technically does not have to be a separate file (and it's a file, not a contract). A file can import itself as a module.

[cameel]

Also, this needs a changelog entry.