CSSRuleList::evaluate_media_queries previously compared
CSSMediaRule::condition_matches() (which reads MediaQuery::m_matches,
default false) against the freshly-computed result. A brand-new @media
rule whose condition matches would therefore look like a false->true
flip the very first time it was evaluated, the same shape as the
CSSStyleSheet outer-MediaList bug fixed in the previous commit.
In practice all known paths that introduce a new @media rule
(StyleSheetList::add_sheet, AdoptedStyleSheets on_set,
CSSStyleSheet::invalidate_owners, CSSImportRule::set_style_sheet) call
through CSSStyleSheet::evaluate_media_queries eagerly and absorb the
flip before the next Document::evaluate_media_rules pass, so this
change does not move counters in the existing tests. It does make the
inner-@media handling consistent with the outer one, and protects any
future path (e.g. CSSGroupingRule::insert_rule into a nested rule
list) where a new @media rule might be evaluated for the first time
during the regular media-rule pass.
Track per-rule whether evaluate has been called yet via a sticky
m_did_evaluate flag on CSSMediaRule, and only record a flip on
subsequent evaluations.
Having the dumping code in a separate Dump.cpp meant that it was often
overlooked when the rules gained new features, and also limits dumping
to publicly-accessible information.
Previously we would always use the window's viewport which was incorrect
if we were within an iframe.
This is likely applicable to all uses of
`Length::ResolutionContext::for_window`.
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
