updating for the comments.

implement wells(), localWellsActive() and wellsActive() for the
BlackoilModelBase and its derived classed.

opm/polymer/fullyimplicit/BlackoilPolymerModel.hpp

@@ -179,6 +179,8 @@ namespace Opm {
 
         // Need to declare Base members we want to use here.
         using Base::stdWells;
+        using Base::wells;
+        using Base::wellsActive;
         using Base::variableState;
         using Base::computePressures;
         using Base::computeGasPressure;