Override RestartGameplay in GameplaySyncMachine for safer use

without overriding here, it uses the natural restarting process
and because of several reasons, that crashes the game (continuity of some things is broken and we get null derefs)

src/Etterna/Screen/Gameplay/ScreenGameplay.h

@@ -106,7 +106,7 @@ class ScreenGameplay : public ScreenWithMenuElements
 	virtual void StageFinished(bool bBackedOut);
 	bool AllAreFailing();
 
-	void RestartGameplay();
+	virtual void RestartGameplay();
 
 	virtual void SetupNoteDataFromRow(Steps* pSteps, int row);
 

src/Etterna/Screen/Gameplay/ScreenGameplaySyncMachine.cpp

@@ -129,6 +129,15 @@ ScreenGameplaySyncMachine::ResetAndRestartCurrentSong()
 	AdjustSync::ResetAutosync();
 }
 
+void
+ScreenGameplaySyncMachine::RestartGameplay()
+{
+	// Override normal RestartGameplay to just do this thing
+	// because otherwise some weird continuity issues arise
+	// and we crash
+	ResetAndRestartCurrentSong();
+}
+
 static LocalizedString OLD_OFFSET("ScreenGameplaySyncMachine", "Old offset");
 static LocalizedString NEW_OFFSET("ScreenGameplaySyncMachine", "New offset");
 static LocalizedString COLLECTING_SAMPLE("ScreenGameplaySyncMachine",

src/Etterna/Screen/Gameplay/ScreenGameplaySyncMachine.h

@@ -16,6 +16,7 @@ class ScreenGameplaySyncMachine : public ScreenGameplayNormal
 
 	void HandleScreenMessage(const ScreenMessage& SM) override;
 	void ResetAndRestartCurrentSong();
+	void RestartGameplay() override;
 
   protected:
 	bool UseSongBackgroundAndForeground() const override { return false; }