fix master - TypeTrait semantic fails for non static aggregate members

[ghost]

Edit: this is no WIP anymore

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[RazvanN7]

At some point, please push a commit containing Fix Issue 19420 so that the bot links the PR with the bugzilla issue. Thanks!

[ghost]

Yes i know @RazvanN7 but for now the bug is not "shipped" so the issue number doesn't need to appear in the changelog, that's why i didn't follow the usual procedure.

[ghost]

Ready for review, please someone remove the WIP label, thx.

[ghost]

All phobos instances of alias ... = AliasSeq!(__traits( can be simplified now and test pass. Good sign that the bug is fixed.

[ghost]

I've found (and fixd) another kind of expressions that needed special processing in my IZ library. (when a ScopeExp is returned by __traits). I cannot try to convert the wholeness of the aliases that can be found in the DUB packages so it will be necessary to ask people to try the new way of aliasing during the beta that will introduce the feature, it's not totally impossible that some special cases still miss and for them the semantic is different of what gave AliasSeq in this that what's aliased is the expression type, because of the final if else falling back to getType.

[ghost]

ping @thewilsonator, green tests.

[ghost]

thx.

[RazvanN7]

@thewilsonator Please do not merge PRs with such haste. I was in the process of reviewing this.

Let aside the review, the PR does not contain the issue number so the bot did not link the bugzilla issue: https://issues.dlang.org/show_bug.cgi?id=19420