Fix error "mb_convert_encoding(): Illegal character encoding specified"

modified:   plugins/af_readability/init.php

plugins/af_readability/init.php

@@ -180,8 +180,12 @@ class Af_Readability extends Plugin {
 			// this is the worst hack yet :(
 			if (strtolower($tmpdoc->encoding) != 'utf-8') {
 				$tmp = preg_replace("/<meta.*?charset.*?\/?>/i", "", $tmp);
+				if (empty($tmpdoc->encoding)) {
+					$tmp = mb_convert_encoding($tmp, 'utf-8');
+				} else {
 					$tmp = mb_convert_encoding($tmp, 'utf-8', $tmpdoc->encoding);
 				}
+			}
 
 			try {
 				$r = new Readability(new Configuration());