Fix some warnings in JS console (#40727)

* Fix warning about passing a ref to a function component
- this didn't work and fortunately was not used (anymore) at all

* Move comment where it belongs

* Fix warning that functions cannot be react children

frontend/src/metabase/app.js

@@ -67,14 +67,12 @@ function _init(reducers, getRoutes, callback) {
   const routes = getRoutes(store);
   const history = syncHistoryWithStore(browserHistory, store);
 
-  let root;
-
   createTracker(store);
 
   initializeEmbedding(store);
 
   ReactDOM.render(
-    <Provider store={store} ref={ref => (root = ref)}>
+    <Provider store={store}>
       <EmotionCacheProvider>
         <DragDropContextProvider backend={HTML5Backend} context={{ window }}>
           <ThemeProvider>
@@ -91,7 +89,7 @@ function _init(reducers, getRoutes, callback) {
 
   store.dispatch(refreshSiteSettings());
 
-  PLUGIN_APP_INIT_FUCTIONS.forEach(init => init({ root }));
+  PLUGIN_APP_INIT_FUCTIONS.forEach(init => init());
 
   window.Metabase = window.Metabase || {};
   window.Metabase.store = store;

frontend/src/metabase/visualizations/components/TableInteractive/TableInteractive.jsx

@@ -710,9 +710,9 @@ class TableInteractive extends Component {
 
     return (
       <TableDraggable
-        /* needs to be index+name+counter so Draggable resets after each drag */
         enableUserSelectHack={false}
         enableCustomUserSelectHack={!isVirtual}
+        /* needs to be index+name+counter so Draggable resets after each drag */
         key={columnIndex + column.name + DRAG_COUNTER}
         axis="x"
         disabled={!isDraggable}
@@ -1060,7 +1060,7 @@ class TableInteractive extends Component {
                   columnWidth={this.getDisplayColumnWidth}
                   cellRenderer={props =>
                     gutterColumn && props.columnIndex === 0
-                      ? () => null // we need a phantom cell to properly offset columns
+                      ? null // we need a phantom cell to properly offset columns
                       : this.tableHeaderRenderer({
                           ...props,
                           columnIndex: props.columnIndex - gutterColumn,
@@ -1089,7 +1089,7 @@ class TableInteractive extends Component {
                   rowHeight={ROW_HEIGHT}
                   cellRenderer={props =>
                     gutterColumn && props.columnIndex === 0
-                      ? () => null // we need a phantom cell to properly offset columns
+                      ? null // we need a phantom cell to properly offset columns
                       : this.cellRenderer({
                           ...props,
                           columnIndex: props.columnIndex - gutterColumn,