fix render_textarea support view objects if schema changed

jsonform/gadget_json_generated_form_child.js

@@ -101,13 +101,13 @@
     return input;
   }
 
-  function render_textarea(json_field, default_value, data_format) {
+  function render_textarea(json_document, data_format) {
     var input = document.createElement("textarea");
-    if (default_value !== undefined) {
-      if (default_value instanceof Array) {
-        input.value = default_value.join("\n");
+    if (json_document !== undefined) {
+      if (typeof json_document === "object") {
+        input.value = JSON.stringify(json_document, null, 2);
       } else {
-        input.value = default_value;
+        input.value = json_document;
       }
     }
     input["data-format"] = data_format;
@@ -674,11 +674,11 @@
 
     if (!input && ["string", "integer", "number"].indexOf(type) >= 0) {
       if (json_field.contentMediaType === "text/plain") {
-        input = render_textarea(json_field, default_value, "string");
+        input = render_textarea(default_value, "string");
       } else {
         input = document.createElement("input");
         if (default_value !== undefined) {
-          if (["object", "array"].indexOf(getDocumentType(default_value)) >= 0) {
+          if (typeof default_value === "object") {
             default_value = JSON.stringify(default_value);
           }
           input.value = default_value;