SL-16094: Fix second startup hang.

Add LLWindowWin32Thread::Post(), like post() except it uses PostMessage() to
send the work item to the window thread. Support this in mainWindowProc().

Move LLWindowWin32::recreateWindow()'s destroy_window_handler() call onto the
window thread. Delaying destruction of the old HWND ensures that we can use
PostMessage() and GetMessage() with that HWND to pass the lambda work item.
Moreover, it's likely to be less buggy to call DestroyWindow() on the same
thread that created the window.

Make recreateWindow()'s window thread lambda bind the window class parameters
by value, rather than binding 'this' and back-referencing LLWindowWin32
members.

Make recreateWindow() construct the window thread lambda and then decide
whether to pass it to the window thread using post() or Post(), depending on
whether we have a current HWND -- therefore whether the window thread is
blocked on GetMessage(). That means we can eliminate the kickWindowThread()
call.

Make destroy_window_handler() accept HWND by value rather than by non-const
reference. Since it doesn't attempt to modify the caller's value, this is a
better match for the function's semantics anyway -- but importantly, it lets
us pass a const HWND.

0 files changed, 0 insertions, 0 deletions