constify and deautoify more things in vision

This was part of my effort to understand how things work.

Change-Id: I49dae7400fba8ec1f02d006f3d14c6dc254a8187
diff --git a/y2019/vision/constants.h b/y2019/vision/constants.h
index 1e0380b..a56e9b3 100644
--- a/y2019/vision/constants.h
+++ b/y2019/vision/constants.h
@@ -60,9 +60,9 @@
 struct DatasetInfo {
   int camera_id;
   // In meters from IMU start.
-  std::array<double, 2> to_tape_measure_start;
+  ::std::array<double, 2> to_tape_measure_start;
   // In meters,
-  std::array<double, 2> tape_measure_direction;
+  ::std::array<double, 2> tape_measure_direction;
   // This will multiply tape_measure_direction and thus has no units.
   double beginning_tape_measure_reading;
   const char *filename_prefix;
@@ -85,7 +85,7 @@
 // Get the IDs of the cameras in each port for a particular teensy board.
 // inlined so that we don't have to deal with including it in the autogenerated
 // constants.cc.
-inline std::array<int, 5> CameraSerialNumbers(uint32_t processor_id) {
+inline ::std::array<int, 5> CameraSerialNumbers(uint32_t processor_id) {
   switch (processor_id) {
     case CodeBotTeensyId():
       return {{0, 0, 0, 16, 19}};