UI: Add "Active Sources Only" option to adv audio props

Allows the ability to modify the properties of inactive audio sources
which may in scenes other than the one that is currently active.

UI/window-basic-adv-audio.hpp

@@ -3,6 +3,8 @@
 #include <obs.hpp>
 #include <QDialog>
 #include <vector>
+#include <QCheckBox>
+#include <QPointer>
 
 class OBSAdvAudioCtrl;
 class QGridLayout;
@@ -15,8 +17,10 @@ class OBSBasicAdvAudio : public QDialog {
 private:
 	QWidget *controlArea;
 	QGridLayout *mainLayout;
+	QPointer<QCheckBox> activeOnly;
 	OBSSignal sourceAddedSignal;
 	OBSSignal sourceRemovedSignal;
+	bool showInactive;
 
 	std::vector<OBSAdvAudioCtrl *> controls;
 
@@ -33,8 +37,10 @@ public slots:
 
 	void ShowContextMenu(const QPoint &pos);
 	void SetVolumeType();
+	void ActiveOnlyChanged(bool checked);
 
 public:
 	OBSBasicAdvAudio(QWidget *parent);
 	~OBSBasicAdvAudio();
+	void SetShowInactive(bool showInactive);
 };