Qt/Settings: Implement audio pane

Source/Core/DolphinQt2/Settings/AudioPane.h

@@ -0,0 +1,59 @@
+// Copyright 2017 Dolphin Emulator Project
+// Licensed under GPLv2+
+// Refer to the license.txt file included.
+
+#pragma once
+
+#include <QWidget>
+
+class QCheckBox;
+class QComboBox;
+class QLabel;
+class QGridLayout;
+class QRadioButton;
+class QSlider;
+class QSpinBox;
+class SettingsWindow;
+
+class AudioPane final : public QWidget
+{
+  Q_OBJECT
+public:
+  explicit AudioPane();
+
+  void OnEmulationStateChanged(bool running);
+
+private:
+  void CreateWidgets();
+  void ConnectWidgets();
+
+  void LoadSettings();
+  void SaveSettings();
+
+  void OnBackendChanged();
+  void OnVolumeChanged(int volume);
+
+  QGridLayout* m_main_layout;
+
+  // DSP Engine
+  QRadioButton* m_dsp_hle;
+  QRadioButton* m_dsp_lle;
+  QRadioButton* m_dsp_interpreter;
+
+  // Volume
+  QSlider* m_volume_slider;
+  QLabel* m_volume_indicator;
+
+  // Backend
+  QLabel* m_backend_label;
+  QComboBox* m_backend_combo;
+  QCheckBox* m_dolby_pro_logic;
+  QLabel* m_latency_label;
+  QSpinBox* m_latency_spin;
+
+  // Audio Stretching
+  QCheckBox* m_stretching_enable;
+  QLabel* m_stretching_buffer_label;
+  QSlider* m_stretching_buffer_slider;
+  QLabel* m_stretching_buffer_indicator;
+};