Don't look for the ESP8266 if running unit tests.

Fact* espVersion = getFact(FactSystem::ParameterProvider, MAV_COMP_ID_UDP_BRIDGE, "SW_VER"); crashes unit test if the parameter does not exist (which is exactly what the call is trying to establish).

src/AutoPilotPlugins/PX4/PX4AutoPilotPlugin.cc

@@ -104,12 +104,24 @@ const QVariantList& PX4AutoPilotPlugin::vehicleComponents(void)
             _components.append(QVariant::fromValue((VehicleComponent*)_radioComponent));
 
             //-- Is there an ESP8266 Connected?
+#ifdef QT_DEBUG
+#ifndef __mobile__
+            //-- Unit test barfs if I ask for a parameter that does not exists. The whole poing of the
+            //   test below is to behave differently if ESP8266 is present or not.
+    if (!qgcApp()->runningUnitTests()) {
+#endif
+#endif
             Fact* espVersion = getFact(FactSystem::ParameterProvider, MAV_COMP_ID_UDP_BRIDGE, "SW_VER");
             if(espVersion && espVersion->componentId() == MAV_COMP_ID_UDP_BRIDGE) {
                 _esp8266Component = new PX4ESP8266Component(_vehicle, this);
                 _esp8266Component->setupTriggerSignals();
                 _components.append(QVariant::fromValue((VehicleComponent*)_esp8266Component));
             }
+#ifdef QT_DEBUG
+#ifndef __mobile__
+    }
+#endif
+#endif
 
             _flightModesComponent = new FlightModesComponent(_vehicle, this);
             _flightModesComponent->setupTriggerSignals();