Viewer: Remove hidden ViewOnlyControl parameter

This was implemented in 190ca33
(TurboVNC 2.0 beta1) for a customer whose portal exposed the option in
another way.  It is not a generally useful feature, and the company in
question is no longer using TurboVNC.

java/com/turbovnc/rfb/Params.java

@@ -679,11 +679,6 @@ public void save(String node) {
  "Ignore all keyboard and mouse events in the viewer window and do not " +
  "pass those events to the VNC server.", false);
 
- // Set to 0 to disable the view-only checkbox in the Options dialog
- public BoolParameter viewOnlyControl =
- new BoolParameter("ViewOnlyControl", this, false,
- null, true);
-
  // DISPLAY PARAMETERS
 
  private HeaderParameter displayHeader =

java/com/turbovnc/vncviewer/OptionsDialog.java

@@ -381,7 +381,6 @@ class OptionsDialog extends Dialog implements ActionListener, ChangeListener,
 
  viewOnly = new JCheckBox("View only (ignore mouse & keyboard)");
  viewOnly.addItemListener(this);
- viewOnly.setEnabled(params.viewOnlyControl.get());
 
  Dialog.addGBComponent(viewOnly, inputPanel,
  0, 0, 2, 1, 2, 2, 1, 0,