fix(object-widget): highlight nested validation errors

When building nested controls for fields in an object widget, ensure the
object's ID is passed through as a 'parent' so that errors in nested
fields can be linked to the parent.

This ensures that a validation error on a field within an object will
"bubble up" and show an error on a collapsed object's control in the
editor, helping users to identify where there are validation errors.

packages/decap-cms-widget-object/src/ObjectControl.js

@@ -89,6 +89,7 @@ export default class ObjectControl extends React.Component {
       isFieldHidden,
       locale,
       collapsed,
+      forID,
     } = this.props;
 
     if (field.get('widget') === 'hidden') {
@@ -112,7 +113,7 @@ export default class ObjectControl extends React.Component {
         onValidate={onValidateObject}
         processControlRef={controlRef && controlRef.bind(this)}
         controlRef={controlRef}
-        parentIds={parentIds}
+        parentIds={[...parentIds, forID]}
         isDisabled={isDuplicate}
         isHidden={isHidden}
         isFieldDuplicate={isFieldDuplicate}