Added guessing of mailto/tel schemes

app/src/main/java/eu/faircode/email/FragmentDialogOpenLink.java

@@ -141,7 +141,14 @@ public class FragmentDialogOpenLink extends FragmentDialogBase {
 
         final Uri uri;
         if (_uri.getScheme() == null) {
-            Uri g = Uri.parse(URLUtil.guessUrl(_uri.toString()));
+            String url = _uri.toString();
+            if (Helper.EMAIL_ADDRESS.matcher(url).matches())
+                uri = Uri.parse("mailto:" + _uri.toString());
+            else if (android.util.Patterns.PHONE.matcher(url).matches())
+                // Alternative: PhoneNumberUtils.isGlobalPhoneNumber()
+                uri = Uri.parse("tel:" + _uri.toString());
+            else {
+                Uri g = Uri.parse(URLUtil.guessUrl(url));
                 String scheme = g.getScheme();
                 if (scheme != null) {
                     if ("http".equals(scheme))
@@ -149,6 +156,7 @@ public class FragmentDialogOpenLink extends FragmentDialogBase {
                     uri = Uri.parse(scheme + "://" + _uri.toString());
                 } else
                     uri = _uri;
+            }
         } else
             uri = _uri;