Auto merge of #14971 - asajeffrey:script-track-active-documents, r=cbrewster

Constellation informs script about documents becoming inactive, active or fully active.

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This PR replaces the current freeze/thaw mechanism by messages from the constellation to script informing it about when documents become inactive, active or fully active.

This means we can now implement |Document::is_active()| which is used in |document.write|.

This PR also changes how timers work: previously they were initialized running, and were then frozen/thawed. This means there was a transitory period when timers were running even though the document was not fully active. With this PR, timers are initially suspended, and are only resumed when the document is made fully active.

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- [X] `./mach build -d` does not report any errors
- [X] `./mach test-tidy` does not report any errors
- [X] These changes fix #14876
- [X] These changes do not require tests because it's an interal refactoring.

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1 files changed, 2 insertions, 2 deletions

diff --git a/components/script/dom/bindings/trace.rs b/components/script/dom/bindings/trace.rs
index 6d268823d77..6e0ce0d47dc 100644
--- a/components/script/dom/bindings/trace.rs
+++ b/components/script/dom/bindings/trace.rs
@@ -74,7 +74,7 @@ use profile_traits::time::ProfilerChan as TimeProfilerChan;
 use script_layout_interface::OpaqueStyleAndLayoutData;
 use script_layout_interface::reporter::CSSErrorReporter;
 use script_layout_interface::rpc::LayoutRPC;
-use script_traits::{TimerEventId, TimerSource, TouchpadPressurePhase};
+use script_traits::{DocumentActivity, TimerEventId, TimerSource, TouchpadPressurePhase};
 use script_traits::{UntrustedNodeAddress, WindowSizeData, WindowSizeType};
 use serde::{Deserialize, Serialize};
 use servo_atoms::Atom;
@@ -327,7 +327,7 @@ unsafe_no_jsmanaged_fields!(TrustedPromise);
 unsafe_no_jsmanaged_fields!(PropertyDeclarationBlock);
 // These three are interdependent, if you plan to put jsmanaged data
 // in one of these make sure it is propagated properly to containing structs
-unsafe_no_jsmanaged_fields!(FrameId, FrameType, WindowSizeData, WindowSizeType, PipelineId);
+unsafe_no_jsmanaged_fields!(DocumentActivity, FrameId, FrameType, WindowSizeData, WindowSizeType, PipelineId);
 unsafe_no_jsmanaged_fields!(TimerEventId, TimerSource);
 unsafe_no_jsmanaged_fields!(TimelineMarkerType);
 unsafe_no_jsmanaged_fields!(WorkerId);