internal/frontend: don't report errors from serveUnitPage

Don't invoke the errorreporting API for errors from serveUnitPage.
Otherwise we'll be doing it for every 404.

Change-Id: I9a973e23654bfa20a98cb8efcde4c46c44501d20
Reviewed-on: https://go-review.googlesource.com/c/pkgsite/+/280624
Trust: Jonathan Amsterdam <jba@google.com>
Run-TryBot: Jonathan Amsterdam <jba@google.com>
Reviewed-by: Julie Qiu <julie@golang.org>
TryBot-Result: kokoro <noreply+kokoro@google.com>
diff --git a/internal/frontend/unit.go b/internal/frontend/unit.go
index cf545f1..e69fe38 100644
--- a/internal/frontend/unit.go
+++ b/internal/frontend/unit.go
@@ -75,7 +75,7 @@
 // modules, documentation, readmes, licenses, and package_imports tables.
 func (s *Server) serveUnitPage(ctx context.Context, w http.ResponseWriter, r *http.Request,
 	ds internal.DataSource, info *urlPathInfo) (err error) {
-	defer derrors.WrapAndReport(&err, "serveUnitPage(ctx, w, r, ds, %v)", info)
+	defer derrors.Wrap(&err, "serveUnitPage(ctx, w, r, ds, %v)", info)
 
 	tab := r.FormValue("tab")
 	if tab == "" {