make compatible with gadget api

gadget_json_generated_form.js

@@ -498,6 +498,15 @@
     })
 
     .declareMethod('render', function (options) {
+      return this.changeState({
+        key: options.key,
+        value: options.value || "",
+        schema: options.schema,
+        schema_url: options.schema_url,
+        editable: options.editable === undefined ? true : options.editable
+      });
+    })
+    .onStateChange(function (options) {
       var g = this;
       g.props.toplevel = true;
       // contain map of current normalized schema
@@ -586,7 +595,25 @@
     })
 
     .declareMethod('getContent', function () {
-      return this.props.form_gadget.getContent();
+      var g = this;
+      if (g.state.editable) {
+        return g.props.form_gadget.getContent()
+          .push(function (value) {
+            // Change the value state in place
+            // This will prevent the gadget to be changed if
+            // its parent call render with the same value
+            // (as ERP5 does in case of formulator error)
+            g.state.value = value;
+            if (g.state.key) {
+              var form_data = {};
+              value = JSON.stringify(value);
+              form_data[g.state.key] = value;
+              return form_data;
+            }
+            return value;
+          });
+      }
+      return {};
     });
 
 }(window, document, location, rJS, RSVP, jIO, tv4));
\ No newline at end of file