diff --git a/tests/utils.h b/tests/utils.h
index f6b7174..dcb08f5 100644
--- a/tests/utils.h
+++ b/tests/utils.h
@@ -316,6 +316,8 @@
 
 bool IsLowRamDevice();
 
+int64_t NanoTime();
+
 class Errno {
  public:
   Errno(int e) : errno_(e) {}