Always update schema data in redux as the underlying data may have ch…

…anged regardless of its ID set matching

Fixes silverstripe#960

client/src/components/UploadField/UploadField.js

@@ -59,18 +59,8 @@ class UploadField extends Component {
   }
 
   componentDidMount() {
-    // Copy form schema data into redux and then ignore it
-    const { id, data, actions, value, files } = this.props;
-
-    // If the data within the "files" prop already matches the value then we don't need to copy
-    // schema data into redux
-    if (
-      value && value.Files && files && value.Files.length === files.length
-      && files.filter(file => !value.Files.includes(file.id)).length === 0
-    ) {
-      return;
-    }
-
+    // Copy form schema data into redux
+    const { id, data, actions } = this.props;
     actions.uploadField.setFiles(id, data.files);
   }