android: fix lock not showing (#3181)

* android: fix lock not showing

* better fix

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/App.kt

@@ -149,7 +149,7 @@ fun MainScreen() {
       LaunchedEffect(Unit) {
         // With these constrains when user presses back button while on ChatList, activity destroys and shows auth request
         // while the screen moves to a launcher. Detect it and prevent showing the auth
-        if (!(AppLock.destroyedAfterBackPress.value && chatModel.controller.appPrefs.laMode.get() == LAMode.SYSTEM)) {
+        if (!(androidIsFinishingMainActivity() && chatModel.controller.appPrefs.laMode.get() == LAMode.SYSTEM)) {
           AppLock.runAuthenticate()
         }
       }

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/AppLock.kt

@@ -24,7 +24,6 @@ object AppLock {
 
   // Remember result and show it after orientation change
   val laFailed = mutableStateOf(false)
-  val destroyedAfterBackPress = mutableStateOf(false)
 
   fun clearAuthState() {
     userAuthorized.value = null

apps/multiplatform/common/src/commonMain/kotlin/chat/simplex/common/platform/UI.kt

@@ -14,3 +14,5 @@ expect fun LocalMultiplatformView(): Any?
 @Composable
 expect fun getKeyboardState(): State<KeyboardState>
 expect fun hideKeyboard(view: Any?)
+
+expect fun androidIsFinishingMainActivity(): Boolean