Implement new popover inside invoker behaviour

https://bugs.webkit.org/show_bug.cgi?id=283494

Reviewed by NOBODY (OOPS!).

This patch matches the new spec behaviour for when a popover is inside its invoker.

See whatwg/html#10770

* LayoutTests/imported/w3c/web-platform-tests/html/semantics/popovers/popover-nested-in-button-expected.txt:
* Source/WebCore/html/HTMLButtonElement.cpp:
(WebCore::HTMLButtonElement::defaultEventHandler):
* Source/WebCore/html/HTMLFormControlElement.cpp:
(WebCore::HTMLFormControlElement::handlePopoverTargetAction const):
* Source/WebCore/html/HTMLFormControlElement.h:
* Source/WebCore/html/HTMLInputElement.cpp:
(WebCore::HTMLInputElement::defaultEventHandler):

LayoutTests/imported/w3c/web-platform-tests/html/semantics/popovers/popover-nested-in-button-expected.txt

@@ -1,6 +1,6 @@
 Button   Button
 
-FAIL clicking a popover nested inside a button should not re-invoke the popover assert_true: Should still be open expected true got false
+PASS clicking a popover nested inside a button should not re-invoke the popover
 PASS corner case: invoker that is also a popover
-FAIL invoker inside popover still works, even with weird nesting assert_true: descendant doesn't close popover expected true got false
+PASS invoker inside popover still works, even with weird nesting
 

Source/WebCore/html/HTMLButtonElement.cpp

@@ -172,7 +172,7 @@ void HTMLButtonElement::defaultEventHandler(Event& event)
         }
 
         if (!(protectedForm && m_type == SUBMIT))
-            handlePopoverTargetAction();
+            handlePopoverTargetAction(event.target());
 
     }
 

Source/WebCore/html/HTMLFormControlElement.cpp

@@ -395,24 +395,29 @@ void HTMLFormControlElement::setPopoverTargetAction(const AtomString& value)
 }
 
 // https://html.spec.whatwg.org/#popover-target-attribute-activation-behavior
-void HTMLFormControlElement::handlePopoverTargetAction() const
+void HTMLFormControlElement::handlePopoverTargetAction(const EventTarget* eventTarget) const
 {
-    RefPtr target = popoverTargetElement();
-    if (!target)
+    RefPtr popover = popoverTargetElement();
+    if (!popover)
         return;
 
-    ASSERT(target->popoverData());
+    ASSERT(popover->popoverData());
+
+    if (RefPtr eventTargetNode = dynamicDowncast<Node>(eventTarget)) {
+        if (popover->containsIncludingShadowDOM(eventTargetNode.get()) && popover->isDescendantOrShadowDescendantOf(this))
+            return;
+    }
 
     auto action = popoverTargetAction();
     bool canHide = action == hideAtom() || action == toggleAtom();
-    bool shouldHide = canHide && target->popoverData()->visibilityState() == PopoverVisibilityState::Showing;
+    bool shouldHide = canHide && popover->popoverData()->visibilityState() == PopoverVisibilityState::Showing;
     bool canShow = action == showAtom() || action == toggleAtom();
-    bool shouldShow = canShow && target->popoverData()->visibilityState() == PopoverVisibilityState::Hidden;
+    bool shouldShow = canShow && popover->popoverData()->visibilityState() == PopoverVisibilityState::Hidden;
 
     if (shouldHide)
-        target->hidePopover();
+        popover->hidePopover();
     else if (shouldShow)
-        target->showPopover(this);
+        popover->showPopover(this);
 }
 
 RefPtr<Element> HTMLFormControlElement::commandForElement() const

Source/WebCore/html/HTMLFormControlElement.h

@@ -130,7 +130,7 @@ class HTMLFormControlElement : public HTMLElement, public ValidatedFormListedEle
 
     void dispatchBlurEvent(RefPtr<Element>&& newFocusedElement) override;
 
-    void handlePopoverTargetAction() const;
+    void handlePopoverTargetAction(const EventTarget*) const;
 
     CommandType commandType() const;
     void handleCommand();

Source/WebCore/html/HTMLInputElement.cpp

@@ -1362,7 +1362,7 @@ void HTMLInputElement::defaultEventHandler(Event& event)
         if (commandForElement())
             handleCommand();
         else
-            handlePopoverTargetAction();
+            handlePopoverTargetAction(event.target());
         if (event.defaultHandled())
             return;
     }