Prepare to migrate to google.golang.org/protobuf

Retain a dependency on both libraries until the template is updated.

Change-Id: I2f0618e1773fd504719154e06d41b776cde77894
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/luci-go/+/504746
Reviewed-by: Yuan Zhi <yuanzhi@google.com>
diff --git a/resultdb/proto/v1/BUILD.gn b/resultdb/proto/v1/BUILD.gn
index 5f7ec35..f262f07 100644
--- a/resultdb/proto/v1/BUILD.gn
+++ b/resultdb/proto/v1/BUILD.gn
@@ -33,5 +33,8 @@
   foreach(name, _protos) {
     sources += [ "${name}.pb.go" ]
   }
-  deps = [ "//third_party/golibs:github.com/golang/protobuf" ]
+  deps = [
+    "//third_party/golibs:github.com/golang/protobuf",
+    "//third_party/golibs:google.golang.org/protobuf",
+  ]
 }
diff --git a/resultdb/sink/proto/v1/BUILD.gn b/resultdb/sink/proto/v1/BUILD.gn
index c8f6cda..c916deb 100644
--- a/resultdb/sink/proto/v1/BUILD.gn
+++ b/resultdb/sink/proto/v1/BUILD.gn
@@ -33,6 +33,7 @@
   }
   deps = [
     "//third_party/golibs:github.com/golang/protobuf",
+    "//third_party/golibs:google.golang.org/protobuf",
     "//third_party/luci-go/resultdb/proto/v1:resultdb_proto_go",
   ]
 }