Fix potential bug accepting invalid certificates in reader mode

app/src/main/java/acr/browser/lightning/reading/SHelper.java

@@ -28,6 +28,7 @@ import java.net.URLEncoder;
 import java.security.SecureRandom;
 import java.security.cert.CertificateException;
 import java.security.cert.X509Certificate;
+import java.util.Date;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -417,11 +418,19 @@ class SHelper {
     private static class DefaultTrustManager implements X509TrustManager {
 
         @Override
-        public void checkClientTrusted(X509Certificate[] arg0, String arg1) throws CertificateException {
+        public void checkClientTrusted(X509Certificate[] certs, String arg1) throws CertificateException {
+            Date today = new Date();
+            for (X509Certificate certificate : certs) {
+                certificate.checkValidity(today);
+            }
         }
 
         @Override
-        public void checkServerTrusted(X509Certificate[] arg0, String arg1) throws CertificateException {
+        public void checkServerTrusted(X509Certificate[] certs, String arg1) throws CertificateException {
+            Date today = new Date();
+            for (X509Certificate certificate : certs) {
+                certificate.checkValidity(today);
+            }
         }
 
         @Override