alloy: Include built-in Chrome isolated origins

[amaitland]

Describe the bug

The alloy runtime doesn't set the default built-in isolated origins like Chrome (and the Chrome Runtime).

Loading chrome://process-internals/#site-isolation in Chrome vs cefclient and you'll see there's no default isolations specified

if you run with cefclient.exe --enable-chrome-runtime then the same isolations that Chrome uses are set as default.

To Reproduce
Steps to reproduce the behaviour:

1. Open cefclient.exe
2. Load chrome://process-internals/#site-isolation
3. Observe there aren't any built in isolations

Steps to compare difference in Chrome Runtime:

1. Open cefclient.exe --enable-chrome-runtime
2. Load chrome://process-internals/#site-isolation
3. Observe there are three urls listed as built-in

Expected behavior
It would be nice if the alloy runtime had the same behaviour as the Chrome runtime.

Screenshots

Loading chrome://process-internals/#site-isolation in Chrome I see

In the CEF Sample Application (cefclient) it looks like

Versions (please complete the following information):

• OS: Windows
• CEF M123

Additional context

https://source.chromium.org/chromium/chromium/src/+/main:docs/process_model_and_site_isolation.md;l=205?q=built-in%20isolate-origins&ss=chromium%2Fchromium%2Fsrc

The Chrome doco suggests that implementing ContentBrowserClient::GetOriginsRequiringDedicatedProcess to provide a list of isolated origins.

You can use the --isolate-origins command line arg to workaround the difference.

[magreenblatt]

I don't think there's anything that we need to add here for Alloy.

The chrome.google.com and chromewebstore.google.com URLs are for the extensions webstore (code here), which is not supported by Alloy. The accounts.google.com URL is for Gaia (code here), which is not supported by Alloy. Any additional internal isolated origins (code here) would only be included in Google Chrome branded builds in any case.

[dmitry-azaraev]

From my understanding they are isolated by default in site-per-process mode anyway. Chrome may force isolation policy for specific origins when browser runs in less restricted mode, but it is what is not recommended, and by so there is no need add any origins explicitly.

[amaitland]

The underlying issue appears to be resolved by switching to the Chrome Bootstrap. As the alloy bootstrap is to be removed with the Chrome Bootstrap to replace it, this is now a non issue anyways.

[magreenblatt]

Thanks for the update.