Modelica.Fluid.Sensors.BaseClasses.PartialFlowSensor should have simplified equations if allowFlowReversal = false

[casella]

Modelica.Fluid.Sensors.BaseClasses.PartialFlowSensor currently contains these equations:

ModelicaStandardLibrary/Modelica/Fluid/Sensors.mo

Lines 828 to 835 in ea28ae3

	port_a.h_outflow = inStream(port_b.h_outflow);
	port_b.h_outflow = inStream(port_a.h_outflow);
	port_a.Xi_outflow = inStream(port_b.Xi_outflow);
	port_b.Xi_outflow = inStream(port_a.Xi_outflow);
	port_a.C_outflow = inStream(port_b.C_outflow);
	port_b.C_outflow = inStream(port_a.C_outflow);

In fact, it makes no sense to compute the inStream() quantities at port_a if allowFlowReversal = false, because they will never be used. In that case, we should give them some constant default value.