1578753 - Make the Style Editor support target switching

Status: RESOLVED FIXED

(DevTools :: Style Editor, enhancement, P1)

Description

[Alexandre Poirot [:ochameau]]

Bug 1565263 landed the TargetList API which helps support switching to another target (as well as supporting the additional remote iframe target).
But we should followup in each tool in order to start using this new API.
The very first goal is to:

• stop memoizing the target/targetFront and may be also the target scoped front (inspector, console, thread, storage, ...). Instead we should use toolbox.targetList.targetFront in order to query for the current top level target front.
• support target switching by using TargetList.watchTargets. In a first iteration we would only care about the top level target. In order to do so, we can check for the isTopLevel argument being passed to the two callbacks register to watchTargets:

  this._toolbox.targetList.watchTargets([this._toolbox.targetList.TYPES.FRAME],
    (type, targetFront, isTopLevel) => {
      if (isTopLevel) {
        // A new top level target is available
        // This will be fired on toolbox opening, for the first one,
        // And then, evertime we navigate to another process.
        // For now, you would need `devtools.target-switching.enabled` to be set to true
        // And navigate from any http website to about:robots, which loads into the parent process. Or enable Fission and navigate between two distinct top level domains.
      }
    },
    (type, targetFront, isTopLevel) => {
      if (isTopLevel) {
        // A top level target has been destroyed
      }
    }

See bug 1565263 for how we migrated the console or bug 1578242 for the inspector.

Comment 1

[Daisuke Akatsuka (:daisuke)]

Attachment: Bug 1578753: Use the current target of TargetList. r?jdescottes!,ochameau!

Comment 2

[Daisuke Akatsuka (:daisuke)]

Attachment: Bug 1578753: Reflect the switching of the top-level target. r?jdescottes!,ochameau!

Depends on D56703

Comment 3

[Daisuke Akatsuka (:daisuke)]

Attachment: Bug 1578753: Add a test for top-level target switing. r?jdescottes!,ochameau!

Depends on D56704

Comment 4

[Chris Peterson [:cpeterson]]

Tracking dt-fission-m2 bugs for Fission Nightly (M6)

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/b0b6c99e9cf0
Use the current target of TargetList. r=jdescottes,ochameau
https://hg.mozilla.org/integration/autoland/rev/2297b54080b1
Reflect the switching of the top-level target. r=jdescottes,ochameau
https://hg.mozilla.org/integration/autoland/rev/3cff413b1897
Add a test for top-level target switing. r=jdescottes,ochameau

Comment 6

[Natalia Csoregi [:nataliaCs]]

https://hg.mozilla.org/mozilla-central/rev/b0b6c99e9cf0
https://hg.mozilla.org/mozilla-central/rev/2297b54080b1
https://hg.mozilla.org/mozilla-central/rev/3cff413b1897