When embedding a X window, it's hard to control whether it receives
mouse/keyboard input or not. It seems the X protocol itself makes this
hard (basically due to the outdated design mismatching with modern
toolkits), and we have to take care of these things explicitly.
Simply do this by manually querying and using the parent window event
flags.
This restores some MPlayer behavior (it doesn't add back exactly the
same code, but it's very similar).
This probably has some potential to interfere with libmpv embedding, so
bump the client API minor.
CC: @mpv-player/stable (if applied, client-api-changes.rst has to be
adjusted to include the 0.5.2 release)
This is probably nicer. The actual version number doesn't change (other
than the minor being incremented).
The "| 0UL" is to make the type unsigned long int, like it was before.
The intention is to make it obvious which mpv releases certain changes
will apply to.
Also attempt to fix RST formatting of the list. This is not very proper,
but probably good enough.
