Convert counter viewer to item model, sync filter with event browser

qrenderdoc/Code/Interface/QRDInterface.h

@@ -1049,6 +1049,9 @@ QWidget.
 )");
   virtual QWidget *Widget() = 0;
 
+  DOCUMENT("Updates the duration column if the selected time unit changes.");
+  virtual void UpdateDurationColumn() = 0;
+
 protected:
   IPerformanceCounterViewer() = default;
   ~IPerformanceCounterViewer() = default;