1743362 - Investigate if WillDestroyCurrentMessageLoop is doing what we expect on Windows

Status: NEW

(Core :: IPC, task)

Description

[Jens Stutte [:jstutte]]

See bug 1730374 comment 57:

Hmm, are we sure that WillDestroyCurrentMessageLoop ever does what we expect it to do? The message we print is only conditional with an #ifdef and the existence of the process_ handle, but I see it appearing in the logs I looked at only when we actually block.
We call WillDestroyCurrentMessageLoop only if we had a DestructionObserver registered. So my doubt would be that the normal flow unregisters that observer before we get into MessageLoop::~MessageLoop and that if we get here with a registered observer we always block?

A first step could be to add also a debug message on success to be sure we know where we hang.