I ran TypeScript against our code with `strictNullChecks` on. Most of the errors generated are noise, because TypeScript doesn't understand how our `assert` method works. But some were legitimate bugs. They are fixed in this patch.
This patch introduces Browser Contexts and methods to manage them:
- `browser.createIncognitoBrowserContext()` - to create new incognito
context
- `browser.browserContext()` - to get all existing contexts
- `browserContext.dispose()` - to dispose incognito context.
Fixes#85.
This patch introduces a new `pipe` option to the launcher to connect over a pipe.
In certain environments, exposing web socket for remote debugging is a security risk.
Pipe connection eliminates this risk.
