Add logging when mouse events are not sent when waiting for a context…

… menu to show

https://bugs.webkit.org/show_bug.cgi?id=273862
rdar://127713566

Reviewed by Abrar Rahman Protyasha and Wenson Hsieh.

There have been recent reports that web content has been unresponsive to mouse events. In 274771@main, I
made a change that could be related, but I’m not sure how. If this logging repeatedly appears when the
bug reproduces, we’ll know 274771@main is the cause.

* Source/WebKit/UIProcess/WebPageProxy.cpp:
(WebKit::WebPageProxy::processNextQueuedMouseEvent):

Canonical link: https://commits.webkit.org/278491@main

Source/WebKit/UIProcess/WebPageProxy.cpp

@@ -3534,6 +3534,7 @@ void WebPageProxy::processNextQueuedMouseEvent()
 
 #if ENABLE(CONTEXT_MENUS)
     if (m_waitingForContextMenuToShow) {
+        WEBPAGEPROXY_RELEASE_LOG(MouseHandling, "processNextQueuedMouseEvent: Waiting for context menu to show.");
         mouseEventHandlingCompleted(event.type(), false);
         return;
     }