gRPC migration

Change-Id: I3129ae27d7ee12a23c7046f0d877e8064f2fd7f4
diff --git a/vendor/google.golang.org/protobuf/internal/detrand/rand.go b/vendor/google.golang.org/protobuf/internal/detrand/rand.go
index a904dd1..49c8676 100644
--- a/vendor/google.golang.org/protobuf/internal/detrand/rand.go
+++ b/vendor/google.golang.org/protobuf/internal/detrand/rand.go
@@ -26,6 +26,14 @@
 	return randSeed%2 == 1
 }
 
+// Intn returns a deterministically random integer between 0 and n-1, inclusive.
+func Intn(n int) int {
+	if n <= 0 {
+		panic("must be positive")
+	}
+	return int(randSeed % uint64(n))
+}
+
 // randSeed is a best-effort at an approximate hash of the Go binary.
 var randSeed = binaryHash()