future: Replaces throws by error in promise in future adaptation.
future: Replaces throws by error in promise in future adaptation.

The goal is to avoid having different channels for reporting an error.
We only need to throw an exception when there is no Promise to set in
error.

Change-Id: I64f120899889c00640ff369027958c89e9aacab3
Reviewed-on: http://gerrit.aldebaran.lan/91421
Reviewed-by: jlamotte <70353e7b0c7d18b7fc75605daf0ccba69fcd3222@aldebaran.com>
Reviewed-by: jmonnon <8898eaf233516e520f996a244ca8a12d20f948b1@aldebaran.com>
Tested-by: vincent.palancher <f8ff75e1c61314c499fafa8de0d9e004e87e66b0@external.softbankrobotics.com>
Reviewed-by: vincent.palancher <f8ff75e1c61314c499fafa8de0d9e004e87e66b0@external.softbankrobotics.com>

aldebaran/libqi,aldebaran/libqi,aldebaran/libqi