message: Add GetCoefficient accessors for MassIntegrator and DiffusionIntegrator
diff: @@ -2062,6 +2062,8 @@ public:
  bool SupportsCeed() const { return DeviceCanUseCeed(); }
  bool SupportsBatchedLOR() const { return true; }
  +
  + Coefficient *GetCoefficient() const { return Q; }
  };
  /** Class for local mass matrix assembling a(u,v) := (Q u, v) */
  @@ -2121,6 +2123,8 @@ public:
  ElementTransformation &Trans);
  bool SupportsCeed() const { return DeviceCanUseCeed(); }
  +
  + const Coefficient *GetCoefficient() const { return Q; }
  };
  /** Mass integrator (u, v) restricted to the boundary of a domain */
  