Manager::sendCallTextMessage crashes if used with non existant callId
Issue generated from Tuleap's migration script. Originally submitted by: Guillaume Roguez (guillaume)
Call Manager::sendTextMessage with an inexistant call id cause application to quit with SEGFAULT. This may happen during a call if the client tries to use this API to send a message on a call that just stopped (ex. connection failure)
How to reproduce: Call Manager::sendTextMessage with an inexistant call id.
Note: D-Bus CallManager::sendTextMessage API can be used for that