gfe-relnote: n/a(code clean up) Inline WallTimeNowInUsec().

PiperOrigin-RevId: 244241890
Change-Id: If4bfb85304acddef54ee437ef798abb0cb2eebff
diff --git a/epoll_server/platform/api/epoll_time.h b/epoll_server/platform/api/epoll_time.h
index 95f0407..3d26384 100644
--- a/epoll_server/platform/api/epoll_time.h
+++ b/epoll_server/platform/api/epoll_time.h
@@ -9,7 +9,7 @@
 
 namespace epoll_server {
 
-int64_t WallTimeNowInUsec() { return WallTimeNowInUsecImpl(); }
+inline int64_t WallTimeNowInUsec() { return WallTimeNowInUsecImpl(); }
 
 }  // namespace epoll_server