[BUG] orphan WPEWebProcess eating 100% cpu

[yury-s]

After running our entire suite I routinely see a couple of WPEWebProcess without corresponding browser processes that are running message loops inside InspectorController::didShowNewWindow() and eating 100% CPU:

#0  0x00007f92491f19cf in __GI___poll (fds=0xb52bd0, nfds=2, timeout=0) at ../sysdeps/unix/sysv/linux/poll.c:29
#1  0x00007f924989336e in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#2  0x00007f92498934a3 in g_main_context_iteration () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#3  0x00007f924c1bdcda in WTF::RunLoop::cycle(unsigned int) () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#4  0x00007f924d340917 in WebCore::InspectorController::didShowNewWindow() () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#5  0x00007f924ad8f80a in WebKit::WebPage::show() () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#6  0x00007f924d474074 in WebCore::FrameLoader::continueLoadAfterNewWindowPolicy(WebCore::ResourceRequest const&, WebCore::FormState*, WTF::String const&, WebCore::NavigationAction const&, WebCore::ShouldContinuePolicyCheck, WebCore::AllowNavigationToInvalidURL, WebCore::NewFrameOpenerPolicy) () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#7  0x00007f924d478d20 in WTF::Detail::CallableWrapper<WebCore::FrameLoader::loadURL(WebCore::FrameLoadRequest&&, WTF::String const&, WebCore::FrameLoadType, WebCore::Event*, WTF::RefPtr<WebCore::FormState, WTF::RawPtrTraits<WebCore::FormState>, WTF::DefaultRefDerefTraits<WebCore::FormState> >&&, std::optional<WebCore::PrivateClickMeasurement>&&, WTF::CompletionHandler<void ()>&&)::$_3, void, WebCore::ResourceRequest const&, WTF::WeakPtr<WebCore::FormState, WTF::EmptyCounter>&&, WTF::String const&, WebCore::NavigationAction const&, WebCore::ShouldContinuePolicyCheck>::call(WebCore::ResourceRequest const&, WTF::WeakPtr<WebCore::FormState, WTF::EmptyCounter>&&, WTF::String const&, WebCore::NavigationAction const&, WebCore::ShouldContinuePolicyCheck) ()
    at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#8  0x00007f924d49410e in WTF::Detail::CallableWrapper<WebCore::FrameLoader::PolicyChecker::checkNewWindowPolicy(WebCore::NavigationAction&&, WebCore::ResourceRequest&&, WTF::RefPtr<WebCore::FormState, WTF::RawPtrTraits<WebCore::FormState>, WTF::DefaultRefDerefTraits<WebCore::FormState> >&&, WTF::String const&, WTF::CompletionHandler<void (WebCore::ResourceRequest const&, WTF::WeakPtr<WebCore::FormState, WTF::EmptyCounter>&&, WTF::String const&, WebCore::NavigationAction const&, WebCore::ShouldContinuePolicyCheck)>&&)::$_7, void, WebCore::PolicyAction, WebCore::PolicyCheckIdentifier>::call(WebCore::PolicyAction, WebCore::PolicyCheckIdentifier) () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#9  0x00007f924ada9416 in WebKit::WebFrame::didReceivePolicyDecision(unsigned long, WebKit::PolicyDecision&&) () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#10 0x00007f924a8acbcb in WebKit::WebPage::didReceiveWebPageMessage(IPC::Connection&, IPC::Decoder&) () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#11 0x00007f924aa682ab in IPC::MessageReceiverMap::dispatchMessage(IPC::Connection&, IPC::Decoder&) () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#12 0x00007f924acb47a7 in WebKit::WebProcess::didReceiveMessage(IPC::Connection&, IPC::Decoder&) () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#13 0x00007f924aa610ba in IPC::Connection::dispatchMessage(std::unique_ptr<IPC::Decoder, std::default_delete<IPC::Decoder> >) () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#14 0x00007f924aa61397 in IPC::Connection::dispatchOneIncomingMessage() () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#15 0x00007f924c155f50 in WTF::RunLoop::performWork() () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#16 0x00007f924c1be146 in WTF::RunLoop::RunLoop()::$_1::__invoke(void*) () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#17 0x00007f924c1bd63a in WTF::RunLoop::$_0::__invoke(_GSource*, int (*)(void*), void*) () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#18 0x00007f924989304e in g_main_context_dispatch () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#19 0x00007f9249893400 in  () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#20 0x00007f92498936f3 in g_main_loop_run () at /usr/lib/x86_64-linux-gnu/libglib-2.0.so.0
#21 0x00007f924c1bdbdb in WTF::RunLoop::run() () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#22 0x00007f924adc41bb in int WebKit::AuxiliaryProcessMain<WebKit::WebProcessMainWPE>(int, char**) () at /home/yurys/webkit/WebKitBuild/WPE/Release/lib/libWPEWebKit-1.0.so.3
#23 0x00007f92491030b3 in __libc_start_main (main=0x401130 <main>, argc=3, argv=0x7ffef8a612d8, init=<optimized out>, fini=<optimized out>, rtld_fini=<optimized out>, stack_end=0x7ffef8a612c8) at ../csu/libc-start.c:308
#24 0x000000000040106e in _start ()

[yury-s]

The issue reproduces on this test in isolation:

playwright/tests/library/browsercontext-basic.spec.ts

Lines 150 to 166 in c200321

	it('should not report frameless pages on error', async ({ browser, server }) => {
	const context = await browser.newContext();
	const page = await context.newPage();
	server.setRoute('/empty.html', (req, res) => {
	res.end(`<a href="${server.EMPTY_PAGE}" target="_blank">Click me</a>`);
	});
	let popup;
	context.on('page', p => popup = p);
	await page.goto(server.EMPTY_PAGE);
	await page.click('"Click me"');
	await context.close();
	if (popup) {
	// This races on Firefox :/
	expect(popup.isClosed()).toBeTruthy();
	expect(popup.mainFrame()).toBeTruthy();
	}
	});