Fix position_sensor_sim's latched_pot value
I noticed it was changing every cycle, which is inaccurate and was
bothering me.
Change-Id: I288ce04ba43d4907a82f9e6c235357d7467e4dde
diff --git a/aos/testing/random_seed.h b/aos/testing/random_seed.h
new file mode 100644
index 0000000..825e7b1
--- /dev/null
+++ b/aos/testing/random_seed.h
@@ -0,0 +1,15 @@
+#ifndef AOS_TESTING_RANDOM_SEED_H_
+#define AOS_TESTING_RANDOM_SEED_H_
+
+namespace aos {
+namespace testing {
+
+// Returns the random seed to use for testing.
+//
+// This is ${TEST_RANDOM_SEED} if it is set or 1.
+int RandomSeed();
+
+} // namespace testing
+} // namespace aos
+
+#endif // AOS_TESTING_RANDOM_SEED_H_