Bug 1843035: part 1) Align unbinding a popover node from the tree closer to the spec. r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D183381

dom/html/nsGenericHTMLElement.cpp

@@ -489,10 +489,8 @@ nsresult nsGenericHTMLElement::BindToTree(BindContext& aContext,
 void nsGenericHTMLElement::UnbindFromTree(bool aNullParent) {
   if (IsInComposedDoc()) {
     // https://html.spec.whatwg.org/#dom-trees:hide-popover-algorithm
-    // If removedNode's popover attribute is not in the no popover state, then
-    // run the hide popover algorithm given removedNode, false, false, and
-    // false.
-    if (GetPopoverData()) {
+    AssertPopoverAttributeStateCorrespondsToAttributePresence();
+    if (GetPopoverAttributeState() != PopoverAttributeState::None) {
       HidePopoverWithoutRunningScript();
     }
     RegUnRegAccessKey(false);
@@ -3211,16 +3209,14 @@ bool nsGenericHTMLElement::PopoverOpen() const {
 bool nsGenericHTMLElement::CheckPopoverValidity(
     PopoverVisibilityState aExpectedState, Document* aExpectedDocument,
     ErrorResult& aRv) {
+  AssertPopoverAttributeStateCorrespondsToAttributePresence();
   const PopoverData* data = GetPopoverData();
   if (!data ||
       data->GetPopoverAttributeState() == PopoverAttributeState::None) {
-    MOZ_ASSERT(!HasAttr(nsGkAtoms::popover));
     aRv.ThrowNotSupportedError("Element is in the no popover state");
     return false;
   }
 
-  MOZ_ASSERT(HasAttr(nsGkAtoms::popover));
-
   if (data->GetPopoverVisibilityState() != aExpectedState) {
     return false;
   }
@@ -3250,6 +3246,20 @@ bool nsGenericHTMLElement::CheckPopoverValidity(
   return true;
 }
 
+void nsGenericHTMLElement::
+    AssertPopoverAttributeStateCorrespondsToAttributePresence() const {
+#ifdef DEBUG
+  if (GetPopoverAttributeState() == PopoverAttributeState::None) {
+    MOZ_ASSERT(!HasAttr(nsGkAtoms::popover));
+  } else {
+    MOZ_ASSERT(HasAttr(nsGkAtoms::popover));
+  }
+#else
+  {
+  }
+#endif  // DEBUG
+}
+
 PopoverAttributeState nsGenericHTMLElement::GetPopoverAttributeState() const {
   return GetPopoverData() ? GetPopoverData()->GetPopoverAttributeState()
                           : PopoverAttributeState::None;