[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/go.etcd.io/etcd/wal/walpb/record.proto b/vendor/go.etcd.io/etcd/wal/walpb/record.proto
new file mode 100644
index 0000000..b694cb2
--- /dev/null
+++ b/vendor/go.etcd.io/etcd/wal/walpb/record.proto
@@ -0,0 +1,20 @@
+syntax = "proto2";
+package walpb;
+
+import "gogoproto/gogo.proto";
+
+option (gogoproto.marshaler_all) = true;
+option (gogoproto.sizer_all) = true;
+option (gogoproto.unmarshaler_all) = true;
+option (gogoproto.goproto_getters_all) = false;
+
+message Record {
+	optional int64 type  = 1 [(gogoproto.nullable) = false];
+	optional uint32 crc  = 2 [(gogoproto.nullable) = false];
+	optional bytes data  = 3;
+}
+
+message Snapshot {
+	optional uint64 index = 1 [(gogoproto.nullable) = false];
+	optional uint64 term  = 2 [(gogoproto.nullable) = false];
+}