Fix crash in SeparatePanel destruction.

We should destroy layers before panel widget destructor started.
We do it already for MainWindow in clearWidgetsHook.

Telegram/SourceFiles/export/view/export_view_panel_controller.cpp

@@ -133,6 +133,13 @@ PanelController::PanelController(not_null<Controller*> process)
 	}, _lifetime);
 }
 
+PanelController::~PanelController() {
+	if (_saveSettingsTimer.isActive()) {
+		saveSettings();
+	}
+	_panel->destroyLayer();
+}
+
 void PanelController::activatePanel() {
 	_panel->showAndActivate();
 }
@@ -386,11 +393,5 @@ void PanelController::saveSettings() const {
 	Local::WriteExportSettings(settings);
 }
 
-PanelController::~PanelController() {
-	if (_saveSettingsTimer.isActive()) {
-		saveSettings();
-	}
-}
-
 } // namespace View
 } // namespace Export

Telegram/SourceFiles/export/view/export_view_panel_controller.h

@@ -35,6 +35,7 @@ class Panel;
 class PanelController {
 public:
 	PanelController(not_null<Controller*> process);
+	~PanelController();
 
 	void activatePanel();
 	void stopWithConfirmation(FnMut<void()> callback = nullptr);
@@ -49,8 +50,6 @@ public:
 		return ContentFromState(_process->state());
 	}
 
-	~PanelController();
-
 private:
 	void fillParams(const PasswordCheckState &state);
 	void stopExport();

Telegram/SourceFiles/ui/widgets/separate_panel.cpp

@@ -291,11 +291,21 @@ void SeparatePanel::ensureLayerCreated() {
 	) | rpl::filter([=] {
 		return _layer != nullptr; // Last hide finish is sent from destructor.
 	}) | rpl::start_with_next([=] {
-		if (Ui::InFocusChain(_layer)) {
+		destroyLayer();
+	}, _layer->lifetime());
+}
+
+void SeparatePanel::destroyLayer() {
+	if (!_layer) {
+		return;
+	}
+
+	auto layer = base::take(_layer);
+	const auto resetFocus = Ui::InFocusChain(layer);
+	if (resetFocus) {
 		setFocus();
 	}
-		_layer = nullptr;
+	layer = nullptr;
-	}, _layer->lifetime());
 }
 
 void SeparatePanel::showInner(base::unique_qptr<Ui::RpWidget> inner) {

Telegram/SourceFiles/ui/widgets/separate_panel.h

@@ -41,6 +41,7 @@ public:
 		LayerOptions options,
 		anim::type animated);
 	void showToast(const QString &text);
+	void destroyLayer();
 
 	rpl::producer<> backRequests() const;
 	rpl::producer<> closeRequests() const;