Differential Revision: https://phabricator.services.mozilla.com/D164656

Bug 1790542 - [devtools] Do not allow redirects on the 'sourceMappingUrl' r=jdescottes,devtools-reviewers

- Block redirects on sourceMappingUrl
- Add debugger test

Differential Revision: https://phabricator.services.mozilla.com/D168648

Bug 1790542 - [devtools] Convert browser_source_map-reload.js test from using .sjs files to createTestHTTPServer r=ochameau,devtools-reviewers

.sjs files depend on redirects to load static files.
In D168648 we block redirects on sourceMappingUrl, so this browser_source_map-reload.js
fails because we use .sjs to serve the content.

This patch refactors to no longer use .sjs files

Differential Revision: https://phabricator.services.mozilla.com/D169739

GC can mutate this vector so don't allow that while we are iterating. I think
it would be safe to use index-based iteration but it's safer to just ban it
entirely.

This fixes the crash produced by the testcase.

Differential Revision: https://phabricator.services.mozilla.com/D169701

Bug 1816158 - Part 2: Require no GC when giving out references to the realm's debugger vector r=sfink

To prevent any other instances of this problme we can update the getDebuggers()
methods on the global and the realm to require no GC.

Depends on D169701

Differential Revision: https://phabricator.services.mozilla.com/D169702