[FIX] service.server: drop idle connection attempts

Avoid wasting HTTP workers (in prefork server mode)
for pending/idle connections.
HTTP connections that have not sent anything for 500ms
will be dropped.

In particular, wkhtmltopdf uses a connection pool
to load remote resources. It opens more HTTP connections
than necessary and uses a random subset of them, leaving
the other idle.

On a server that has little available workers this
may significantly delay report rendering, and could
even lead to a deadlock.

OPW-667870

openerp/service/server.py

@@ -773,6 +773,7 @@ class WorkerHTTP(Worker):
     """ HTTP Request workers """
     def process_request(self, client, addr):
         client.setblocking(1)
+        client.settimeout(0.5)
         client.setsockopt(socket.IPPROTO_TCP, socket.TCP_NODELAY, 1)
         # Prevent fd inherientence close_on_exec
         flags = fcntl.fcntl(client, fcntl.F_GETFD) | fcntl.FD_CLOEXEC