Move Stopwatch to libnetdutils

Move Stopwatch to libnetdutils as it is an useful utility across
netd and the resolver library.

Bug: 128662167
Test: system/netd/tests/runtests.sh passed

Change-Id: Iebaffc66202fbe3a787ca645847762af1ed94bd7
diff --git a/tests/binder_test.cpp b/tests/binder_test.cpp
index c656e1c..682e1b3 100644
--- a/tests/binder_test.cpp
+++ b/tests/binder_test.cpp
@@ -53,11 +53,11 @@
 
 #include "InterfaceController.h"
 #include "NetdConstants.h"
-#include "Stopwatch.h"
 #include "TestUnsolService.h"
 #include "XfrmController.h"
 #include "android/net/INetd.h"
 #include "binder/IServiceManager.h"
+#include "netdutils/Stopwatch.h"
 #include "netdutils/Syscalls.h"
 #include "tun_interface.h"
 
@@ -89,6 +89,7 @@
 using android::net::TunInterface;
 using android::net::UidRangeParcel;
 using android::netdutils::sSyscalls;
+using android::netdutils::Stopwatch;
 
 static const char* IP_RULE_V4 = "-4";
 static const char* IP_RULE_V6 = "-6";