Bug 1946547 - Consider pages which have played media as being interacted with for the back-button intervention. r=farre,dom-core,media-playback-reviewers,alwu

Differential Revision: https://phabricator.services.mozilla.com/D239470

dom/html/HTMLMediaElement.cpp

@@ -4632,6 +4632,8 @@ already_AddRefed<Promise> HTMLMediaElement::Play(ErrorResult& aRv) {
     mAllowedToPlayPromise.ResolveIfExists(true, __func__);
     PlayInternal(handlingUserInput);
     UpdateCustomPolicyAfterPlayed();
+
+    MaybeMarkSHEntryAsUserInteracted();
   } else {
     AUTOPLAY_LOG("reject MediaElement %p to play", this);
     AsyncRejectPendingPlayPromises(NS_ERROR_DOM_MEDIA_NOT_ALLOWED_ERR);
@@ -6372,6 +6374,8 @@ void HTMLMediaElement::RunAutoplay() {
   DispatchAsyncEvent(u"play"_ns);
 
   DispatchAsyncEvent(u"playing"_ns);
+
+  MaybeMarkSHEntryAsUserInteracted();
 }
 
 bool HTMLMediaElement::IsActuallyInvisible() const {
@@ -8087,6 +8091,15 @@ void HTMLMediaElement::NodeInfoChanged(Document* aOldDoc) {
   nsGenericHTMLElement::NodeInfoChanged(aOldDoc);
 }
 
+void HTMLMediaElement::MaybeMarkSHEntryAsUserInteracted() {
+  if (media::AutoplayPolicy::GetAutoplayPolicy(*this) ==
+      dom::AutoplayPolicy::Allowed) {
+    // Only mark entries when autoplay is allowed for both audio and video,
+    // i.e. when AutoplayPolicy is not Blocked or Allowed_muted.
+    OwnerDoc()->SetSHEntryHasUserInteraction(true);
+  }
+}
+
 #ifdef MOZ_WMF_CDM
 bool HTMLMediaElement::IsUsingWMFCDM() const { return mIsUsingWMFCDM; };