test: deflake flaky tests on linux (#44383)

spec/api-browser-window-spec.ts

@@ -942,12 +942,11 @@ describe('BrowserWindow module', () => {
             'did-frame-navigate',
             'did-navigate'
           ];
-          const allEvents = Promise.all(navigationEvents.map(event =>
+          const allEvents = Promise.all(expectedEventOrder.map(event =>
             once(w.webContents, event).then(() => firedEvents.push(event))
           ));
-          const timeout = setTimeout(1000);
           w.loadURL(url);
-          await Promise.race([allEvents, timeout]);
+          await allEvents;
           expect(firedEvents).to.deep.equal(expectedEventOrder);
         });
 

spec/crash-spec.ts

@@ -4,7 +4,7 @@ import * as cp from 'node:child_process';
 import * as fs from 'node:fs';
 import * as path from 'node:path';
 
-import { ifit } from './lib/spec-helpers';
+import { ifit, waitUntil } from './lib/spec-helpers';
 
 const fixturePath = path.resolve(__dirname, 'fixtures', 'crash-cases');
 
@@ -57,11 +57,11 @@ const shouldRunCase = (crashCase: string) => {
 };
 
 describe('crash cases', () => {
-  afterEach(() => {
+  afterEach(async () => {
     for (const child of children) {
       child.kill();
     }
-    expect(children).to.have.lengthOf(0, 'all child processes should have exited cleanly');
+    await waitUntil(() => (children.length === 0));
     children.length = 0;
   });
   const cases = fs.readdirSync(fixturePath);