LibProxy: Fix compile error from "-Wexit-time-destructors" flag

Author: kunlinglio

Libraries/LibCore/Forward.h

@@ -47,8 +47,6 @@ class UDPServer;
 class UDPSocket;
 class WeakEventLoopReference;
 
-struct ProxyData;
-
 #ifdef AK_OS_MACH
 class MachPort;
 #endif

Libraries/LibProxy/CMakeLists.txt

@@ -3,7 +3,6 @@ set(SOURCES
     ProxyManager.cpp
     Platform/ProxyPlatform.cpp
     Platform/ProxyEnv.cpp
-    Platform/ProxyEnv.cpp
 )
 
 if (APPLE)

Libraries/LibProxy/Proxy.cpp

@@ -7,6 +7,7 @@
 #include "Proxy.h"
 #include "Platform/ProxyPlatform.h"
 #include "ProxyManager.h"
+#include <AK/Atomic.h>
 #include <AK/String.h>
 #include <AK/StringUtils.h>
 #include <AK/StringView.h>

Libraries/LibProxy/ProxyManager.cpp

@@ -5,11 +5,12 @@
  */
 
 #include "ProxyManager.h"
+#include <AK/NeverDestroyed.h>
+#include <LibSync/Once.h>
 
 namespace Proxy {
 
 ProxyManager* ProxyManager::s_the = nullptr;
-Sync::OnceFlag ProxyManager::s_once {};
 
 ProxyManager::ProxyManager()
 {
@@ -20,7 +21,8 @@ ProxyManager::ProxyManager()
 
 ProxyManager& ProxyManager::the()
 {
-    Sync::call_once(s_once, [] {
+    static NeverDestroyed<Sync::OnceFlag> s_once;
+    Sync::call_once(*s_once, [] {
         s_the = new ProxyManager();
     });
     return *s_the;

Libraries/LibProxy/ProxyManager.h

@@ -12,7 +12,6 @@
 #include <AK/NonnullRefPtr.h>
 #include <AK/RefPtr.h>
 #include <LibSync/Mutex.h>
-#include <LibSync/Once.h>
 
 namespace Proxy {
 
@@ -28,7 +27,6 @@ class ProxyManager {
 
 private:
     static ProxyManager* s_the;
-    static Sync::OnceFlag s_once;
 
     Sync::Mutex m_proxy_table_lock;
     AK::RefPtr<SystemProxyTable> m_proxy_tables;