bug #3123433 [interface] Avoid double escaping of MySQL errors.

The PMA_DBI_getError function already does escaping, so there is no need
to escape that string again on displaying.

ChangeLog

@@ -123,6 +123,7 @@
 - bug #3115519 [interface] Prevent long queries from being shown in confirmation popup
 - patch #3112792 [navi] Left panel table grouping incorrect,
   thanks to garas - garas
+- bug #3123433 [interface] Avoid double escaping of MySQL errors.
 
 3.3.9.0 (not yet released)
 - bug [doc] Fix references to MySQL doc

libraries/common.lib.php

@@ -617,7 +617,6 @@ function PMA_mysqlDie($error_message = '', $the_query = '',
     } // end if
 
     if (!empty($error_message)) {
-        $error_message = htmlspecialchars($error_message);
         $error_message = preg_replace("@((\015\012)|(\015)|(\012)){3,}@", "\n\n", $error_message);
     }
     // modified to show the help on error-returns

sql.php

@@ -377,12 +377,12 @@ if (isset($GLOBALS['show_as_php']) || !empty($GLOBALS['validatequery'])) {
                 $table = '';
             }
             $active_page = $goto;
-            $message = PMA_Message::rawError(htmlspecialchars($error));
+            $message = PMA_Message::rawError($error);
 
             if( $GLOBALS['is_ajax_request'] == true) {
                 PMA_ajaxResponse($message, false);
             }
-            
+
             /**
              * Go to target path.
              */