[Development] Qt for WebAssembly

[Ulf Hermann]

>> https://codereview.qt-project.org/181112
> not sure why anyone would want to stop/block execution of the one and
> only thread.

sleep() and friends do have a place in single threaded applications. You can use them to do some backoff mechanism when waiting for an external event. You shouldn't do that when user interaction is allowed, but there is no reason not to have them in the API. Furthermore, not having them makes things more complicated as we are using them ourselves and some code would have to be wrapped in #ifdef to compile without them. Btw, if you look at the patch, you'll notice it doesn't actually add or remove any code. It only moves #ifdefs around.

>> https://codereview.qt-project.org/180973
>> https://codereview.qt-project.org/180971
>> https://codereview.qt-project.org/180972
>  ^ these we already have :)

... I guess I have to try "configure -no-feature-thread" again and see what happens.

Ulf