[VOL-2235] Mocks and interfaces for rw-core

This update consists of mocks that are used by the rw-core
during unit testing.  It also includes interfaces used for unit
tests.

Change-Id: I20ca1455c358113c3aa897acc6355e0ddbc614b7
diff --git a/vendor/github.com/modern-go/reflect2/go_below_19.go b/vendor/github.com/modern-go/reflect2/go_below_19.go
new file mode 100644
index 0000000..b050ef7
--- /dev/null
+++ b/vendor/github.com/modern-go/reflect2/go_below_19.go
@@ -0,0 +1,14 @@
+//+build !go1.9
+
+package reflect2
+
+import (
+	"unsafe"
+)
+
+//go:linkname makemap reflect.makemap
+func makemap(rtype unsafe.Pointer) (m unsafe.Pointer)
+
+func makeMapWithSize(rtype unsafe.Pointer, cap int) unsafe.Pointer {
+	return makemap(rtype)
+}