/** Called when the stack frame is entered. */
 public void onEnter(Context cx, Scriptable scope, Scriptable thisObj, Object[] args) {
   contextData.pushFrame(this);
   this.scope = scope;
   this.thisObj = thisObj;
   if (dim.breakOnEnter) {
     dim.handleBreakpointHit(this, cx);
   }
 }