crypto/x509: reduce test's sought number of system certs

150 is too high for some people.

Reports of 132, 145, 149 on OS X.

Fixes #18203

Change-Id: I559639aba7e87e07d1a1249f8b212b3f34a078ab
Reviewed-on: https://go-review.googlesource.com/34019Reviewed-by: Russ Cox <rsc@golang.org>

src/crypto/x509/root_darwin_test.go

@@ -26,11 +26,14 @@ func TestSystemRoots(t *testing.T) {
 		if tt == nil {
 			t.Fatal("no system roots")
 		}
-		// On Mavericks, there are 212 bundled certs; require only
-		// 150 here, since this is just a sanity check, and the
-		// exact number will vary over time.
+		// On Mavericks, there are 212 bundled certs, at least
+		// there was at one point in time on one machine.
+		// (Maybe it was a corp laptop with extra certs?)
+		// Other OS X users report
+		// 135, 142, 145...  Let's try requiring at least 100,
+		// since this is just a sanity check.
 		t.Logf("got %d roots", len(tt.certs))
-		if want, have := 150, len(tt.certs); have < want {
+		if want, have := 100, len(tt.certs); have < want {
 			t.Fatalf("want at least %d system roots, have %d", want, have)
 		}
 	}