&& operator behavior

[ulugbekna]

In react, it's common to write TSX as { myVar && <MyComponent myVar={myVar} />} for optional rendering.

We support such construct, but with current implementation

... 
return <> { '' && <MyComponent /> } </>; 

will return an empty string, which is quite error prone - I learned this from having a bug report.

This also differs from react behavior where { '' && <Component />} results in not rendering the component - ref.

Should we align react and our tsx behavior? @joyceerhl