Add field name to TargetMap flatbuffer

We'll use this to know which map we're using in code once we load it on
the robot.

Signed-off-by: Milind Upadhyay <milind.upadhyay@gmail.com>
Change-Id: Id54b82e7b7f07b767a84e266d47468973cbe319e
diff --git a/frc971/vision/target_mapper_test.cc b/frc971/vision/target_mapper_test.cc
index 37b037b..f56cd8d 100644
--- a/frc971/vision/target_mapper_test.cc
+++ b/frc971/vision/target_mapper_test.cc
@@ -12,6 +12,7 @@
 namespace {
 constexpr double kToleranceMeters = 0.05;
 constexpr double kToleranceRadians = 0.05;
+constexpr std::string_view kFieldName = "test";
 }  // namespace
 
 #define EXPECT_POSE_NEAR(pose1, pose2)             \
@@ -219,7 +220,7 @@
           .first;
 
   frc971::vision::TargetMapper mapper(target_poses, target_constraints);
-  mapper.Solve();
+  mapper.Solve(kFieldName);
 
   ASSERT_EQ(mapper.target_poses().size(), 2);
   EXPECT_POSE_NEAR(mapper.target_poses()[0], MakePose(5.0, 0.0, M_PI));
@@ -253,7 +254,7 @@
           .first;
 
   frc971::vision::TargetMapper mapper(target_poses, target_constraints);
-  mapper.Solve();
+  mapper.Solve(kFieldName);
 
   ASSERT_EQ(mapper.target_poses().size(), 2);
   EXPECT_POSE_NEAR(mapper.target_poses()[0], MakePose(5.0, 0.0, M_PI));
@@ -284,7 +285,7 @@
           .first;
 
   frc971::vision::TargetMapper mapper(target_poses, target_constraints);
-  mapper.Solve();
+  mapper.Solve(kFieldName);
 
   ASSERT_EQ(mapper.target_poses().size(), 2);
   EXPECT_POSE_NEAR(mapper.target_poses()[0], MakePose(5.0, 0.0, M_PI));
@@ -375,7 +376,7 @@
                                          timestamped_target_detections)
           .first;
   frc971::vision::TargetMapper mapper(target_poses, target_constraints);
-  mapper.Solve();
+  mapper.Solve(kFieldName);
 
   for (auto [target_pose_id, mapper_target_pose] : mapper.target_poses()) {
     TargetMapper::TargetPose actual_target_pose =
@@ -399,7 +400,7 @@
 
   frc971::vision::TargetMapper mapper_bad_poses(target_poses,
                                                 target_constraints);
-  mapper_bad_poses.Solve();
+  mapper_bad_poses.Solve(kFieldName);
 
   for (auto [target_pose_id, mapper_target_pose] :
        mapper_bad_poses.target_poses()) {