The Context selector drop down should also display regular (non-remote) frames that are loaded from the same domain as the top level document.

Honza

Tracking dt-fission-m3-mvp bugs for Fission M8 (blocking Release channel experiment, but not Beta experiment).

This bug is about instantiating BrowsingContextTarget actors for in-process iframes.

Today, we only instantiate one per process.
Typically, one for the top level document, and one per remote iframe.
If the top level document contains iframes in the same origin, they will be debugged via the top level document's target.
Similarly, if the remote iframe contains iframes in the same remote origin, they will be debugger by the remote iframe's target.

Now, with this bug, we would like to spawn one target for all documents, all iframes.
This will be much easier to follow, but it can be a performance regression and may be features that do not currently work fine with remote iframes.

This may depend on bug 1644397, which will introduce the first JSWindowActor targets for top level targets and implement target switching on the server side.

Moving "dt-fission-m3-reserve" bugs to "dt-fission-future" because they don't block Fission MVP.

Morphing this bug into a more generic framework task.
Doing the framework bits should automatically get the javascript context selector to work with same-process iframes.

This patch introduces a new pref, devtools.every-frame-target.enabled,
that when set to true will cause target actors to be created on every
iframe, no matter if they are remote or not, no matter if Fission is
enabled or not.

This adds a ignoreSubFrames property on the BrowsingContextActor so
it can focus solely on the docShell it was passed.

https://hg.mozilla.org/mozilla-central/rev/dce1f891a11f