Merge pull request #3247 from lujiaxing/patch-1

Update image.js to make image uploader send same header with drag-drop-uploading

dialogs/image/image.js

@@ -702,7 +702,7 @@
             uploader.on('uploadBeforeSend', function (file, data, header) {
                 //这里可以通过data对象添加POST参数
                 if (actionUrl.toLowerCase().indexOf('jsp') != -1) {
-                    header['X_Requested_With'] = 'XMLHttpRequest';
+                    header['X-Requested-With'] = 'XMLHttpRequest';
                 }
             });