(core) Fixing cursor position for filtered linked section.

Summary:
In a selector table, when a selected row is filtered out of view, linked widgets should update based on the newly selected row.
There were a few bugs that contributed to this wrong behavior:
- Gridview wasn't subscribing to the current row id, and the row with id 'new' was being converted to the first row
- Cursor was keeping track of the currently selected row id, it was hiding a problem behind the proper rowIndex
- Undo/redo somehow leveraged the wrong rowId from the cursor during the position restore.

The `No data` text was also changed to be more meaningful.

Test Plan: Added and updated.

Reviewers: georgegevoian

Reviewed By: georgegevoian

Differential Revision: https://phab.getgrist.com/D3937

app/client/components/GridView.js

@@ -1233,9 +1233,11 @@ GridView.prototype.buildDom = function() {
         kd.style("width", ROW_NUMBER_WIDTH + 'px'),
         dom('div.gridview_data_row_info',
           kd.toggleClass('linked_dst', () => {
+            const myRowId = row.id();
+            const linkedRowId = self.linkedRowId();
             // Must ensure that linkedRowId is not null to avoid drawing on rows whose
             // row ids are null.
-            return self.linkedRowId() && self.linkedRowId() === row.getRowId();
+            return linkedRowId && linkedRowId === myRowId;
           })
         ),
         kd.text(function() { return row._index() + 1; }),