Added AppLifecycleListener.appWilExit API

platform/platform-impl/src/com/intellij/ide/AppLifecycleListener.java

@@ -55,6 +55,11 @@ public interface AppLifecycleListener {
    */
   void appClosing();
 
+  /**
+   * Fired after all exit checks and after saving the settings. At this point the app is guaranteed to exit.
+   */
+  default void appWillExit() { }
+
   abstract class Adapter implements AppLifecycleListener {
     @Override
     public void appFrameCreated(String[] commandLineArgs, @NotNull Ref<Boolean> willOpenProject) { }

platform/platform-impl/src/com/intellij/openapi/application/impl/ApplicationImpl.java

@@ -758,7 +758,8 @@ public class ApplicationImpl extends PlatformComponentManagerImpl implements App
         return;
       }
 
-      getMessageBus().syncPublisher(AppLifecycleListener.TOPIC).appClosing();
+      final AppLifecycleListener publisher = getMessageBus().syncPublisher(AppLifecycleListener.TOPIC);
+      publisher.appClosing();
 
       myDisposeInProgress = true;
 
@@ -768,6 +769,7 @@ public class ApplicationImpl extends PlatformComponentManagerImpl implements App
 
       saveSettings();
 
+      publisher.appWillExit();
 
       boolean success = disposeSelf(!force);
     if (!success || isUnitTestMode() || Boolean.getBoolean("idea.test.guimode")) {