Add tests for IsCertificateError() and IsClientCertificateError().

Change-Id: Iaf2e31c32df0f73a3cc55c42afef3408387804fb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1848417
Commit-Queue: Eric Roman <[email protected]>
Reviewed-by: Ryan Sleevi <[email protected]>
Cr-Commit-Position: refs/heads/master@{#704285}
diff --git a/net/base/net_errors.h b/net/base/net_errors.h
index f24540a..27d8f66 100644
--- a/net/base/net_errors.h
+++ b/net/base/net_errors.h
@@ -38,7 +38,8 @@
 NET_EXPORT std::string ExtendedErrorToString(int error,
                                              int extended_error_code);
 
-// Returns true if |error| is a certificate error code.
+// Returns true if |error| is a certificate error code. Note this does not
+// include errors for client certificates.
 NET_EXPORT bool IsCertificateError(int error);
 
 // Returns true if |error| is a client certificate authentication error. This