Cherry-pick eeef2a2. rdar://123468009

    Close extension popup web views when the web content process terminates or window.close is called
    https://bugs.webkit.org/show_bug.cgi?id=270130
    rdar://123468009

    Reviewed by Timothy Hatcher.

    On iOS, this will lead to the UIViewController being closed, which leads to a better experience for the client.

    On Mac, if the web view lives in an NSPanel, WebKit will close the window that the web view is in.

    * Source/WebKit/UIProcess/Extensions/Cocoa/WebExtensionActionCocoa.mm:
    (-[_WKWebExtensionActionWebViewDelegate webViewWebContentProcessDidTerminate:]):
    (-[_WKWebExtensionActionWebViewDelegate webViewDidClose:]):

    Canonical link: https://commits.webkit.org/275360@main

Source/WebKit/UIProcess/Extensions/Cocoa/WebExtensionActionCocoa.mm

@@ -142,15 +142,15 @@ - (void)webViewWebContentProcessDidTerminate:(WKWebView *)webView
     if (!_webExtensionAction)
         return;
 
-    _webExtensionAction->popupDidClose();
+    _webExtensionAction->closePopupWebView();
 }
 
 - (void)webViewDidClose:(WKWebView *)webView
 {
     if (!_webExtensionAction)
         return;
 
-    _webExtensionAction->popupDidClose();
+    _webExtensionAction->closePopupWebView();
 }
 
 @end
@@ -672,10 +672,18 @@ - (void)_dismissPopup
 void WebExtensionAction::closePopupWebView()
 {
     [m_popupWebView _close];
+
 #if PLATFORM(IOS_FAMILY)
     [m_popupViewController dismissViewControllerAnimated:YES completion:nil];
 #endif
 
+#if PLATFORM(MAC)
+    auto *window = m_popupWebView.get().window;
+    // FIXME: Instead of checking this window type, this should be handled more like iOS.
+    if ([window isKindOfClass:NSPanel.class])
+        [window close];
+#endif
+
     popupDidClose();
 }