Made StateFeedbackControllerConstants just a set of constants.

Change-Id: I0b7de27749f28ba75349cd8c6b3a80036f3dc04c
diff --git a/frc971/control_loops/drivetrain/polydrivetrain.cc b/frc971/control_loops/drivetrain/polydrivetrain.cc
index 654ca2c..d3a220b 100644
--- a/frc971/control_loops/drivetrain/polydrivetrain.cc
+++ b/frc971/control_loops/drivetrain/polydrivetrain.cc
@@ -153,9 +153,9 @@
 
   constexpr int kHighGearController = 3;
   const Eigen::Matrix<double, 2, 2> FF_high =
-      loop_->controller(kHighGearController).plant.B().inverse() *
+      loop_->controller(kHighGearController).plant.B.inverse() *
       (Eigen::Matrix<double, 2, 2>::Identity() -
-       loop_->controller(kHighGearController).plant.A());
+       loop_->controller(kHighGearController).plant.A);
 
   ::Eigen::Matrix<double, 1, 2> FF_sum = FF.colwise().sum();
   int min_FF_sum_index;
@@ -178,9 +178,9 @@
 
   constexpr int kHighGearController = 3;
   const Eigen::Matrix<double, 2, 2> FF_high =
-      loop_->controller(kHighGearController).plant.B().inverse() *
+      loop_->controller(kHighGearController).plant.B.inverse() *
       (Eigen::Matrix<double, 2, 2>::Identity() -
-       loop_->controller(kHighGearController).plant.A());
+       loop_->controller(kHighGearController).plant.A);
 
   ::Eigen::Matrix<double, 1, 2> FF_sum = FF.colwise().sum();
   int min_FF_sum_index;