eliminate global and file-scope static variables in oct-hist.cc * interpreter.h, interpreter.cc (interpreter::m_history_system, interpreter::get_history_system): New member variable and access function. * interpreter-private.h, interpreter-private.cc (__get_history_system__): New function. * oct-hist.h, oct-hist.cc: Rewrite to use class for command history configuration variables and functions. Change all uses.

--- a/libinterp/parse-tree/lex.ll	Wed Oct 31 18:22:23 2018 -0400
+++ b/libinterp/parse-tree/lex.ll	Wed Oct 31 19:32:41 2018 -0400
@@ -3404,6 +3404,14 @@
       }
   }
 
+  bool
+  base_lexer::input_from_tmp_history_file (void)
+  {
+    history_system& history_sys = m_interpreter.get_history_system ();
+
+    return history_sys.input_from_tmp_file ();
+  }
+
   void
   base_lexer::push_start_state (int state)
   {