diff --git a/android/util.go b/android/util.go
index 92ab845..8fc159d 100644
--- a/android/util.go
+++ b/android/util.go
@@ -20,6 +20,11 @@
 	"strings"
 )
 
+// CopyOf returns a new slice that has the same contents as s.
+func CopyOf(s []string) []string {
+	return append([]string(nil), s...)
+}
+
 func JoinWithPrefix(strs []string, prefix string) string {
 	if len(strs) == 0 {
 		return ""