Upgraded the rest of Time.

Change-Id: I0ee083837e51d8f74a798b7ba14a3b6bb3859f35
diff --git a/y2015/constants.cc b/y2015/constants.cc
index 7ccb020..5b02a25 100644
--- a/y2015/constants.cc
+++ b/y2015/constants.cc
@@ -127,7 +127,8 @@
 const double kArmLength = 0.7366;
 
 // TODO(danielp): All these values might need to change.
-const double kClawPistonSwitchTime = 0.4;
+constexpr ::aos::monotonic_clock::duration kClawPistonSwitchTime =
+    ::std::chrono::milliseconds(400);
 const double kClawZeroingRange = 0.3;
 
 const Values *DoGetValuesForTeam(uint16_t team) {