1487135 - Don't allocate an AuthorStyles for the ShadowRoot of <svg:use>

Status: RESOLVED FIXED

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

Description

[Boris Zbarsky [:bzbarsky]]

It looks like we always allocate an AuthorStyles in the ShadowRoot constructor.  In the case of <svg:use>, we don't do anything with stylesheets in the shadow tree, so the AuthorStyles there is unused.

In fact, maybe we should consider allocating AuthorStyles lazily in general, for all the cases when shadow trees don't have styles inside them.

Comment 1

[Emilio Cobos Álvarez (:emilio)]

Attachment: Make the allocation of AuthorStyles for ShadowRoot lazy.

So that we don't waste a bunch of memory with stuff like <svg:use>. I
plan to shrink AuthorStyles further, but this should help regardless, and isn't
very complex.

Comment 2

[Xidorn Quan [:xidorn] UTC+10]

Comment on attachment 9005065 [details]
Make the allocation of AuthorStyles for ShadowRoot lazy.

Xidorn Quan [:xidorn] UTC+10 has approved the revision.

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/94b793d95409
Make the allocation of AuthorStyles for ShadowRoot lazy. r=xidorn,firefox-style-system-reviewers

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/752786e0dd01
followup: Add a missing check. r=me

Comment 5

[Narcis Beleuzu [:NarcisB]]

https://hg.mozilla.org/mozilla-central/rev/94b793d95409
https://hg.mozilla.org/mozilla-central/rev/752786e0dd01