Fix Android segfault when game exits before TouchScreenGUI is initalized

src/gui/touchscreengui.cpp

@@ -563,6 +563,8 @@ void TouchScreenGUI::init(ISimpleTextureSource *tsrc)
 	m_rarecontrolsbar.addButton(chat_id,      L"Chat", "chat_btn.png");
 	m_rarecontrolsbar.addButton(inventory_id, L"inv",  "inventory_btn.png");
 	m_rarecontrolsbar.addButton(drop_id,      L"drop", "drop_btn.png");
+
+	m_initialized = true;
 }
 
 touch_gui_button_id TouchScreenGUI::getButtonID(s32 x, s32 y)
@@ -725,6 +727,8 @@ void TouchScreenGUI::handleReleaseEvent(size_t evt_id)
 
 void TouchScreenGUI::translateEvent(const SEvent &event)
 {
+	if (!m_initialized)
+		return;
 	if (!m_visible) {
 		infostream
 			<< "TouchScreenGUI::translateEvent got event but not visible!"
@@ -1071,6 +1075,9 @@ void TouchScreenGUI::applyJoystickStatus()
 
 TouchScreenGUI::~TouchScreenGUI()
 {
+	if (!m_initialized)
+		return;
+
 	for (auto &button : m_buttons) {
 		if (button.guibutton) {
 			button.guibutton->drop();
@@ -1096,6 +1103,9 @@ TouchScreenGUI::~TouchScreenGUI()
 
 void TouchScreenGUI::step(float dtime)
 {
+	if (!m_initialized)
+		return;
+
 	// simulate keyboard repeats
 	for (auto &button : m_buttons) {
 		if (!button.ids.empty()) {
@@ -1180,6 +1190,9 @@ void TouchScreenGUI::registerHudItem(int index, const rect<s32> &rect)
 
 void TouchScreenGUI::Toggle(bool visible)
 {
+	if (!m_initialized)
+		return;
+
 	m_visible = visible;
 	for (auto &button : m_buttons) {
 		if (button.guibutton)

src/gui/touchscreengui.h

@@ -201,6 +201,7 @@ public:
 	void show();
 
 private:
+	bool m_initialized = false;
 	IrrlichtDevice *m_device;
 	IGUIEnvironment *m_guienv;
 	IEventReceiver *m_receiver;