Error when using `continue` in else statement inside map comprehension syntax

This is normal array comprehension, which allows to use a `continue ` in else-statement:

```haxe
function doSomething(i:Int) trace("special" + i);
trace([for(i in 0...10) if (i != 5) 'number $i' else { doSomething(i); continue; }]);
```
I want to be able to construct a Map and add a similar else-statement.
I now get a slightly confusing error `Unexpected =>` and `Dynamic should be Void`.
```haxe
function doSomething(i:Int) trace("special" + i);
trace([for (i in 0...10) if (i != 5) i => 'number $i' else { doSomething(i); continue; }]);
```
Seen on Haxe 3.4.2:
Seen on Haxe 4.0.0 preview 1:
(both JS targets)

Reproduce the examples from the linked try.haxe.org and try-haxe.mrcdk.com snippets with Haxe 3.4.2 and Haxe 4.0.0 preview 1 on the JavaScript target. Start by tracing compiler handling for map-comprehension syntax with an else branch and continue. Done means the Map comprehension accepts this form, preserves the continue behavior, and no longer reports the shown errors.

Written by the indexing model from the issue text.