use drupal_json_encode() directly

Author: makara

flot.module

@@ -67,13 +67,13 @@ function theme_flot_graph($variables) {
     $id = str_replace('-', '_', $element['id']);
 
     if ($loader) {
-      $json_data = function_exists('json_encode') ? json_encode($data) : drupal_json_encode($data);
+      $json_data = drupal_json_encode($data);
       $extra = "Drupal.flot.{$id}_data = {$json_data}; {$loader}";
       $data = array();
     }
 
-    $json_data = function_exists('json_encode') ? json_encode($data) : drupal_json_encode($data);
-    $json_options = function_exists('json_encode') ? json_encode($options) : drupal_json_encode($options);
+    $json_data = drupal_json_encode($data);
+    $json_options = drupal_json_encode($options);
     $data = "(function ($) {
       $(document).ready(function() {
         Drupal.flot.{$id} = $.plot($('#{$element['id']}'), {$json_data}, {$json_options});