Add tabs, a performance page and a mixer button to Quick Settings

shell/plugins/panels/quick-settings/TabBar.qml

@@ -0,0 +1,28 @@
+import QtQuick
+import qs.Commons
+import qs.Ui
+
+Row {
+  id: root
+
+  property var tabs: []
+  property string currentTab: ""
+  signal tabRequested(string tabId)
+
+  spacing: Style.spaceReal(6)
+
+  Repeater {
+    model: root.tabs
+
+    Button {
+      required property var modelData
+      width: (root.width - root.spacing * (root.tabs.length - 1)) / root.tabs.length
+      text: modelData.label
+      iconText: modelData.icon
+      selected: modelData.id === root.currentTab
+      bordered: true
+      fontSize: Style.font.bodySmall
+      onClicked: root.tabRequested(modelData.id)
+    }
+  }
+}