Fix DataEntry errors

app/src/frontend/building/data-components/data-entry.tsx

@@ -37,9 +37,12 @@ const DataEntry: React.FunctionComponent<DataEntryProps> = (props) => {
                 disabled={props.mode === 'view' || props.disabled}
                 placeholder={props.placeholder}
                 onChange={e =>
-                    e.target.value === '' ?
-                        null :
-                        props.onChange(props.slug, e.target.value)
+                    props.onChange(
+                        props.slug,
+                        e.target.value === '' ?
+                            null :
+                            e.target.value
+                    )
                 }
             />
         </Fragment>

app/src/frontend/building/data-containers/type.tsx

@@ -42,7 +42,12 @@ const TypeView = (props) => {
             />
             <DataEntry
                 title="Original building use"
+                slug=""
                 tooltip="What was the building originally used for when it was built? I.e. If it was Victorian warehouse which is now an office this would be warehouse"
+                value={undefined}
+                copy={props.copy}
+                mode={props.mode}
+                onChange={props.onUpdate}
                 disabled={true}
             />
         </Fragment>