app/build: add oauth2 to build dashboard

Fixes golang/go#12775

Change-Id: I9ac3870bb27b8dc715fcd0628993965086642b4d
Reviewed-on: https://go-review.googlesource.com/19879
Reviewed-by: Burcu Dogan <jbd@google.com>
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>
diff --git a/app/build/dash.go b/app/build/dash.go
index 2ea4ae8..09ea2fa 100644
--- a/app/build/dash.go
+++ b/app/build/dash.go
@@ -112,6 +112,11 @@
 	},
 	{
 		Kind: "subrepo",
+		Name: "oauth2",
+		Path: "golang.org/x/oauth2",
+	},
+	{
+		Kind: "subrepo",
 		Name: "review",
 		Path: "golang.org/x/review",
 	},