1633723 - Add BrowsingContext::GetParentCrossChromeBoundaryInParent

Status: RESOLVED FIXED

(Core :: DOM: Core & HTML, task)

Description

[Henri Sivonen (:hsivonen)]

I have on multiple occasions encountered code that if simply rewritten from nsIDocShellTreeItem to BrowsingContext fails a bunch of mochitest-browser-chrome tests.

I have left the old code path in place for the chrome process.

The easiest way to get rid of nsIDocShellTreeItem in those cases would be to introduce a method on BrowsingContext that in content processes behaves like GetParent and in the chrome process, if GetParent would return nullptr for a Web content BrowsingContext instead returns the embedder chrome BrowsingContext.

Comment 1

[Nika Layzell [:nika] (ni? for response)]

Attachment: Bug 1633723 - Add CanonicalBrowsingContext::GetParentCrossChromeBoundary,

Comment 2

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/e2e978e59c56
Add CanonicalBrowsingContext::GetParentCrossChromeBoundary, r=kmag

Comment 3

[Alexandru Michis [:malexandru]]

https://hg.mozilla.org/mozilla-central/rev/e2e978e59c56

Comment 4

[Henri Sivonen (:hsivonen)]

Was it intentional to put this on CanonicalBrowsingContext instead of BrowsingContext per comment 0?

Comment 5

[Nika Layzell [:nika] (ni? for response)]

Yes. It's not possible to cross the content/chrome boundary in content processes, which means that this method would be misleading or useless in content processes, so I only included it on CanonicalBrowsingContext.

Comment 6

[Henri Sivonen (:hsivonen)]

I agree that it could be misleading, but it wouldn't be useless when the goal is to pass existing mochitest-browser-chrome tests that expect otherwise the same kind of walk to walk across the XUL boundary in the chrome process and not to in the content processes.

E.g.:
nsFocusManager::GetCommonAncestor

Comment 7

[Nika Layzell [:nika] (ni? for response)]

Cases like that seem uncommon and specialized, and the behaviour could be easily performed at such call-sites, by doing something like:

RefPtr<BrowsingContext> parent = bc->GetParent();
if (!parent && XRE_IsParentProcess()) {
  parent = bc->Canonical()->GetParentCrossChromeBoundary();
}