Toggling CSSStyleSheet::disabled previously cleared the cached media
match bits and reloaded fonts, but never informed the owning documents
or shadow roots that style resolution was now stale. Worse, the IDL
binding for the disabled attribute dispatches through a non-virtual
setter on StyleSheet, so any override on CSSStyleSheet was bypassed
entirely.
Make set_disabled() virtual so the CSSStyleSheet override actually runs,
snapshot the pre-mutation shadow-root stylesheet effects before flipping
the flag, and hand them to invalidate_owners() so a disable that strips
the last host-reaching rule still tears down host-side style correctly.
To prepare for introducing a CSS::URL type, we need to qualify any use
of LibURL as `::URL::foo` instead of `URL::foo` so the compiler doesn't
get confused.
Many of these uses will be replaced, but I don't want to mix this in
with what will likely already be a large change.
Resulting in a massive rename across almost everywhere! Alongside the
namespace change, we now have the following names:
* JS::NonnullGCPtr -> GC::Ref
* JS::GCPtr -> GC::Ptr
* JS::HeapFunction -> GC::Function
* JS::CellImpl -> GC::Cell
* JS::Handle -> GC::Root
Until now we would simply apply stylesheets in the order they finished
loading. This patch adds a StyleSheetList object that hangs off of each
Document and contains all the style sheets in document order.
There's still a lot of work to do for a proper cascade, but at least
this makes us consistently wrong every time. :^)
