The TypeScript transformer elides a bunch of syntax kinds that should not appear in the emitted JavaScript code (e.g. access modifiers, types,...). Normally, this elision would be done by returning undefined from the visitor.

This commit changed the handling for SyntaxKind.Constructor: previously constructors were elided, but now visitConstructor handles them. However, the commit forgot to stop the cases above the SyntaxKind.Constructor case falling through, so now all cases that should just have return undefined actually call visitConstructor instead. Luckily, visitConstructor returns undefined when its argument is not a function-like declaration, which is why the code works and passes the tests... although it works for the wrong reason. 😛

This change re-introduces the missing return undefined statement, so the elided cases no longer fall through to visitConstructor.