Bug 1821732 - implement nearest invlusive target popover for invoker alg, r=emilio

Differential Revision: https://phabricator.services.mozilla.com/D173539

dom/base/nsINode.cpp

@@ -3182,6 +3182,18 @@ Element* nsINode::GetNearestInclusiveOpenPopover() {
   return nullptr;
 }
 
+Element* nsINode::GetNearestInclusiveTargetPopoverForInvoker() {
+  for (auto* el : InclusiveFlatTreeAncestorsOfType<
+           nsGenericHTMLFormControlElementWithState>()) {
+    if (auto* popover = el->GetPopoverTargetElement()) {
+      if (popover->IsAutoPopover() && popover->IsPopoverOpen()) {
+        return popover;
+      }
+    }
+  }
+  return nullptr;
+}
+
 void nsINode::AddAnimationObserver(nsIAnimationObserver* aAnimationObserver) {
   AddMutationObserver(aAnimationObserver);
   OwnerDoc()->SetMayHaveAnimationObservers();

dom/base/nsINode.h

@@ -502,12 +502,17 @@ class nsINode : public mozilla::dom::EventTarget {
 
   MOZ_CAN_RUN_SCRIPT mozilla::dom::Element* GetParentFlexElement();
 
-  /*
+  /**
    * Returns the nearest inclusive open popover for a given node, see
    * https://html.spec.whatwg.org/multipage/popover.html#nearest-inclusive-open-popover
    */
   mozilla::dom::Element* GetNearestInclusiveOpenPopover();
 
+  /**
+   * https://html.spec.whatwg.org/multipage/popover.html#nearest-inclusive-target-popover-for-invoker
+   */
+  mozilla::dom::Element* GetNearestInclusiveTargetPopoverForInvoker();
+
   bool IsNode() const final { return true; }
 
   NS_IMPL_FROMEVENTTARGET_HELPER(nsINode, IsNode())
@@ -518,6 +523,9 @@ class nsINode : public mozilla::dom::EventTarget {
   bool IsElement() const { return GetBoolFlag(NodeIsElement); }
 
   virtual bool IsTextControlElement() const { return false; }
+  virtual bool IsGenericHTMLFormControlElementWithState() const {
+    return false;
+  }
 
   // Returns non-null if this element subclasses `LinkStyle`.
   virtual const mozilla::dom::LinkStyle* AsLinkStyle() const { return nullptr; }

dom/html/nsGenericHTMLElement.h

@@ -1224,6 +1224,10 @@ class nsGenericHTMLFormControlElementWithState
       already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo,
       mozilla::dom::FromParser aFromParser, FormControlType);
 
+  bool IsGenericHTMLFormControlElementWithState() const final { return true; }
+  NS_IMPL_FROMNODE_HELPER(nsGenericHTMLFormControlElementWithState,
+                          IsGenericHTMLFormControlElementWithState())
+
   // nsIContent
   bool ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
                       const nsAString& aValue,