This change is adding a new property on the BrowserContextOptions class called `_debugName`. This property allows defining a user-friendly name for the browser context, and currently it is being used in one place, the Trace Viewer. When user provides the new value in the following way:
```typescript
const { chromium } = require('playwright');
(async () => {
const browser = await chromium.launch();
const context = await browser.newContext({ _traceDir: __dirname, _debugName: 'My custom testcase name' });
await context.close();
await browser.close();
})();
```
The `_debugName` will be saved in the `*.trace` file for this browser context, on the `context-created` event, under the key `debugName`.
Later, when such a trace is displayed using Trace Viewer, the `debugName` will be displayed in the dropdown in the top right part of the app instead of the actual trace filename.
Fixes#5157.
- Instead of capturing snapshots on demand, we now stream them
from each frame every 100ms.
- Certain actions can also force snapshots at particular moment using
"checkpoints".
- Trace viewer is able to show the page snapshot at a particular
timestamp, or using a "checkpoint" snapshot.
- Small optimization to not process stylesheets if CSSOM was not used.
There still is a lot of room for improvement.
When `page.reload()` is racing against the renderer-initiated
navigation, we might end up with `waitForNavigation()` being rejected
before the reload implementation is able to catch it.
To avoid that, carefully use Promise.all and await `waitForNavigation`
from the get go.
Same happens to `page.goForward()` and `page.goBack()`.
This changes quoted text selector like `text="Foo Bar"` to perform
normalized whitespace match.
Most of the time users want to match some string visible on the page,
and that always means normalized whitespace.
We keep the case sensitivity and full-string vs substring difference
between quoted and unquoted matches.
This adds `{Page,Frame}.isChecked(selector)` and `ElementHandle.isChecked()` methods.
Useful to do assertions in tests:
```js
await page.click('text="Add TODO"');
expect(await page.isChecked('.item-done')).toBe(false);
```
These methods are useful for verification in tests, e.g.
```js
expect(await page.isEnabled(':text("Remove All")')).toBe(false);
await page.click(':text("Add Item")');
expect(await page.isVisible('.item:text("new item")')).toBe(true);
expect(await page.isEnabled(':text("Remove All")')).toBe(true);
```
