On Solaris, after browser exit, we often find one or more orphaned
WebKitWebProcess processes that have been reparented by init.  All are
in the SIGSTOP state.

Theoretically, at time of parent exit, Solaris sends a SIGHUP to the
children, but apparently, it is being ignored by WebKitWebProcess when
it is stopped.

This patch prevents the web process cache from stopping these processes.
On Solaris, WebKitWebProcess then terminates when the parent exits.

Ideally, we would find a way to handle this better on Solaris, but for now,
this is preferred to the accumulation of stopped WebProcess workers.

See:
    https://bugs.webkit.org/show_bug.cgi?id=236971
    https://bugs.webkit.org/show_bug.cgi?id=239298

--- a/Source/WebKit/UIProcess/glib/WebProcessProxyGLib.cpp	2022-06-04 19:13:27.000000000 +0000
+++ b/Source/WebKit/UIProcess/glib/WebProcessProxyGLib.cpp	2022-06-10 19:10:37.304290885 +0000
@@ -69,6 +69,10 @@
     sendMessageToWebContextWithReply(WTFMove(message), [](UserMessage&&) { });
 }
 
+#if OS(SOLARIS)
+void WebProcessProxy::platformSuspendProcess() {}
+void WebProcessProxy::platformResumeProcess() {}
+#else
 void WebProcessProxy::platformSuspendProcess()
 {
     auto id = processIdentifier();
@@ -88,5 +92,6 @@
     RELEASE_LOG(Process, "%p - [PID=%i] WebProcessProxy::platformResumeProcess", this, id);
     kill(id, SIGCONT);
 }
+#endif 
 
 } // namespace WebKit