Bug 1674776 - Update DocumentTimeline::mLastRefreshDriverTime outside parallel styling. r=boris,decoder

Note that we can probably use mLastRefreshDriverTime directly in
DocumentTimeline::GetCurrentTimeStamp(), i.e. we don't need to use the refresh
driver there, but I'd preserve the current behavior.

Differential Revision: https://phabricator.services.mozilla.com/D97823

dom/animation/DocumentTimeline.cpp

@@ -49,6 +49,8 @@ DocumentTimeline::DocumentTimeline(Document* aDocument,
   if (mDocument) {
     mDocument->Timelines().insertBack(this);
   }
+  // Ensure mLastRefreshDriverTime is valid.
+  UpdateLastRefreshDriverTime();
 }
 
 DocumentTimeline::~DocumentTimeline() {
@@ -97,6 +99,12 @@ bool DocumentTimeline::TracksWallclockTime() const {
 }
 
 TimeStamp DocumentTimeline::GetCurrentTimeStamp() const {
+  nsRefreshDriver* refreshDriver = GetRefreshDriver();
+  return refreshDriver ? refreshDriver->MostRecentRefresh()
+                       : mLastRefreshDriverTime;
+}
+
+void DocumentTimeline::UpdateLastRefreshDriverTime() {
   nsRefreshDriver* refreshDriver = GetRefreshDriver();
   TimeStamp refreshTime =
       refreshDriver ? refreshDriver->MostRecentRefresh() : TimeStamp();
@@ -125,8 +133,6 @@ TimeStamp DocumentTimeline::GetCurrentTimeStamp() const {
   if (!refreshTime.IsNull()) {
     mLastRefreshDriverTime = refreshTime;
   }
-
-  return result;
 }
 
 Nullable<TimeDuration> DocumentTimeline::ToTimelineTime(
@@ -182,6 +188,7 @@ void DocumentTimeline::MostRecentRefreshTimeUpdated() {
 }
 
 void DocumentTimeline::WillRefresh(mozilla::TimeStamp aTime) {
+  UpdateLastRefreshDriverTime();
   MostRecentRefreshTimeUpdated();
 }
 

dom/animation/DocumentTimeline.h

@@ -68,6 +68,8 @@ class DocumentTimeline final : public AnimationTimeline,
 
   Document* GetDocument() const override { return mDocument; }
 
+  void UpdateLastRefreshDriverTime();
+
   bool IsMonotonicallyIncreasing() const override { return true; }
 
  protected:
@@ -83,7 +85,7 @@ class DocumentTimeline final : public AnimationTimeline,
   // The most recently used refresh driver time. This is used in cases where
   // we don't have a refresh driver (e.g. because we are in a display:none
   // iframe).
-  mutable TimeStamp mLastRefreshDriverTime;
+  TimeStamp mLastRefreshDriverTime;
   bool mIsObservingRefreshDriver;
 
   TimeDuration mOriginTime;

dom/base/Document.cpp

@@ -13236,6 +13236,13 @@ void Document::SetNavigationTiming(nsDOMNavigationTiming* aTiming) {
   if (!mLoadingTimeStamp.IsNull() && mTiming) {
     mTiming->SetDOMLoadingTimeStamp(GetDocumentURI(), mLoadingTimeStamp);
   }
+
+  // If there's already the DocumentTimeline instance, tell it since the
+  // DocumentTimeline is based on both the navigation start time stamp and the
+  // refresh driver timestamp.
+  if (mDocumentTimeline) {
+    mDocumentTimeline->UpdateLastRefreshDriverTime();
+  }
 }
 
 nsContentList* Document::ImageMapList() {

mozglue/build/TsanOptions.cpp

@@ -263,9 +263,6 @@ extern "C" const char* __tsan_default_suppressions() {
          "race:VRShMem::PullBrowserState\n"
          "race:VRShMem::PushBrowserState\n"
 
-         // Bug 1674776
-         "race:DocumentTimeline::GetCurrentTimeAsDuration\n"
-
          // Bug 1607588
          "race:nssToken_Destroy\n"
          "race:nssSlot_GetToken\n"