[lldb] Devirtualize IOHandler::{IsActive,SetIsDone,GetIsDone} (NFC)

[JDevlieghere]

Summary

There are no implementations overriding these methods.

[kastiglione]

good good

lldb/include/lldb/Core/IOHandler.h

public:
 
   // Called when CTRL+C is pressed which usually causes
   // Debugger::DispatchInputInterrupt to be called.
 
   virtual bool Interrupt() = 0;
 
   virtual void GotEOF() = 0;
 
-  virtual bool IsActive() { return m_active && !m_done; }
+  bool IsActive() { return m_active && !m_done; }
 
-  virtual void SetIsDone(bool b) { m_done = b; }
+  void SetIsDone(bool b) { m_done = b; }
 
-  virtual bool GetIsDone() { return m_done; }
+  bool GetIsDone() { return m_done; }
 
   Type GetType() const { return m_type; }
 
   virtual void Activate() { m_active = true; }
 
   virtual void Deactivate() { m_active = false; }
 
   virtual void TerminalSizeChanged() {}