(core) fix up newRec when column names change; autocomplete after newRec

Summary: This treats newRec in the same way as rec in access formulas.

Test Plan: updated test for column renames; autocomplete checked manually.

Reviewers: dsagal

Reviewed By: dsagal

Differential Revision: https://phab.getgrist.com/D2810

test/nbrowser/gristUtils.ts

@@ -1139,6 +1139,12 @@ export async function getTestState(): Promise<TestState> {
   return state || {};
 }
 
+// Get the full text from an element containing an Ace editor.
+export async function getAceText(el: WebElement): Promise<string> {
+  return driver.executeScript('return ace.edit(arguments[0]).getValue()',
+                              el.find('.ace_editor'));
+}
+
 // All users ('user1', etc.) that can be logged in using Session.user().
 export enum TestUserEnum {
   user1 = 'chimpy',