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This commit effectively reverts 9e683f0, and hence un-accepts #19777. While nice in theory, this proposal turned out to have a few problems. Firstly, supplying a result type implicitly coerces the operand to this type -- that's the main point of result types! But for `try`, this is actually a bad idea; we want a redundant `try` to be a compile error, not to silently coerce the non-error value to an error union. In practice, this didn't always happen, because the implementation was buggy anyway; but when it did, it was really quite silly. For instance, `try try ... try .{ ... }` was an accepted expression, with the inner initializer being initially coerced to `E!E!...E!T`. Secondly, the result type inference here didn't play nicely with `return`. If you write `return try`, the operand would actually receive a result type of `E!E!T`, since the `return` gave a result type of `E!T` and the `try` wrapped it in *another* error union. More generally, the problem here is that `try` doesn't know when it should or shouldn't nest error unions. This occasionally broke code which looked like it should work. So, this commit prevents `try` from propagating result types through to its operand. A key motivation for the original proposal here was decl literals; so, as a special case, `try .foo(...)` is still an allowed syntax form, caught by AstGen and specially lowered. This does open the doors to allowing other special cases for decl literals in future, such as `.foo(...) catch ...`, but those proposals are for another time. Resolves: #21991 Resolves: #22633