Apply workaround for Wayland set_queue race

Wayland objects receive events from the server into an event queue.
Unless specified otherwise, events from the server arrive to the event
queue belonging to the parent object. It is beneficial for us to
override this default queue assignment so that we receive only the
events we are interested in.

We currently override the default event queue assignment using
wl_proxy_set_queue after object construction:

struct wl_object *child_object = wl_create_object(parent_object);
wl_proxy_set_queue((struct wl_proxy *)child_object, queue);

There is a race condition here: events may be received into the parent's
queue before we have a chance to perform this override. This will lead
to hangs if we are expecting an event to arrive to our specific queue.
To workaround this issue, we can use a wrapper object to specify the
desired event queue at the time of object creation:

struct wl_object *parent_wrapper = wl_proxy_create_wrapper(parent_object);
wl_proxy_set_queue((struct wl_proxy *)parent_wrapper, queue);
struct wl_object *child_object = wl_create_object(parent_wrapper);

This commit applies this workaround to all object allocations whose
intended event queues differ from the default assignment to avoid the
aforementioned race condition.

Change-Id: I3e6a7c679280f0d66b02ab7eab06a010e9e24b36
Signed-off-by: David Harvey-Macaulay <>
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