fw_e2e_cov_summarizer: add count of unowned tests

BUG=b:165915863
TEST=ran and inspected output

Change-Id: Ia0b118f043360808bf63b67ff188b102d7813c1c
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/crostestutils/+/2367665
Commit-Queue: Kevin Shelton <kmshelton@chromium.org>
Commit-Queue: Greg Edelston <gredelston@google.com>
Tested-by: Kevin Shelton <kmshelton@chromium.org>
Auto-Submit: Kevin Shelton <kmshelton@chromium.org>
Reviewed-by: Greg Edelston <gredelston@google.com>
diff --git a/go/src/firmware/cmd/e2e_coverage_summarizer/fw_e2e_coverage_summarizer.go b/go/src/firmware/cmd/e2e_coverage_summarizer/fw_e2e_coverage_summarizer.go
index 2b01d57..ef64015 100644
--- a/go/src/firmware/cmd/e2e_coverage_summarizer/fw_e2e_coverage_summarizer.go
+++ b/go/src/firmware/cmd/e2e_coverage_summarizer/fw_e2e_coverage_summarizer.go
@@ -323,4 +323,16 @@
 		p := float64(len(existingTests)) / float64((len(issues) + len(existingTests))) * 100
 		log.Printf("Proportion of tests written: %.2f%%", p)
 	}
+	var unowned int
+	broadGroups := []string{
+		"Chrome OS Team",
+		"Intel",
+		"The Chromium OS Authors",
+	}
+	for _, t := range existingTests {
+		if len(t.Authors) == 1 && contains(broadGroups, (t.Authors[0])) {
+			unowned++
+		}
+	}
+	log.Printf("Tests without maintainers:   %d", unowned)
 }