Refactor: move makeParameterName() to common Language base class.

This method was duplicated more or less identically for 4 languages and will
be needed for another one soon, so put it in the base class from which it can
be simply reused instead.

No changes in the program behaviour whatsoever.

Source/Modules/csharp.cxx

@@ -3200,43 +3200,6 @@ public:
     Delete(replacementname);
   }
 
-  /* -----------------------------------------------------------------------------
-   * makeParameterName()
-   *
-   * Inputs: 
-   *   n - Node
-   *   p - parameter node
-   *   arg_num - parameter argument number
-   *   setter  - set this flag when wrapping variables
-   * Return:
-   *   arg - a unique parameter name
-   * ----------------------------------------------------------------------------- */
-
-  String *makeParameterName(Node *n, Parm *p, int arg_num, bool setter) {
-
-    String *arg = 0;
-    String *pn = Getattr(p, "name");
-
-    // Use C parameter name unless it is a duplicate or an empty parameter name
-    int count = 0;
-    ParmList *plist = Getattr(n, "parms");
-    while (plist) {
-      if ((Cmp(pn, Getattr(plist, "name")) == 0))
-        count++;
-      plist = nextSibling(plist);
-    }
-    String *wrn = pn ? Swig_name_warning(p, 0, pn, 0) : 0;
-    arg = (!pn || (count > 1) || wrn) ? NewStringf("arg%d", arg_num) : Copy(pn);
-
-    if (setter && Cmp(arg, "self") != 0) {
-      // Note that in C# properties, the input variable name is always called 'value'
-      Delete(arg);      
-      arg = NewString("value");
-    }
-
-    return arg;
-  }
-
   /* -----------------------------------------------------------------------------
    * emitTypeWrapperClass()
    * ----------------------------------------------------------------------------- */