only increment the metadata line index if you can parse the line

lib/metadata.js

@@ -99,9 +99,9 @@ Meta.createLineHandler = function (ref, errorHandler) {
         }
 
         if (Array.isArray(line)) {
-            ref.index++;
             try {
                 handleCommand(ref.meta, line);
+                ref.index++;
             } catch (err2) {
                 errorHandler("METADATA_COMMAND_ERR", {
                     error: err2.stack,