Cannot evaluate constant referred by several module aliases

[blitz-1306]

Environment

Any

Scenario

1. Have a file A.sol, that declares file-level constant uint constant X = 100;.
2. Have a file B.sol, that imports A.sol and aliases it as A.
3. Have a file C.sol, that:
   • imports B.sol and aliases it as B.
   • declares file-level constant uint constant Y = 50 + B.A.X;
4. Run constant evaluator on Y

Expected behavior

Expected Y to resolve to 150

Current behavior

Get two crashes:

• InferType would crash here:

  solc-typed-ast/src/types/infer.ts

  Lines 1299 to 1305 in f467859

  	assert(
  	normalT !== undefined,
  	"Unknown field {0} on {1} of type {2}",
  	node.memberName,
  	node,
  	baseT
  	);

• evalConstantExpr() would crash as it cannot proceed evaluation without a type:

  solc-typed-ast/src/types/eval_const.ts

  Lines 403 to 407 in f467859

  	if (e instanceof EvalError && e.expr === undefined) {
  	e.expr = node;
  	}
  	throw e;

Description

See #225 (comment)

Suggested solution

1. Probably reintroduce ModuleType (that is not in package distribution and used for tests only).
2. Fix InferType.
3. Fix evalConstantExpr() to handle tree of MemberAcceeses, that refers to a variable via multiple aliases.