Marcos: Make Utils.asciify(...) avialable to MarcoExpander

The Util.asciify(...) method takes a string and returns an
ASCII only string for the input. All ASCII characters are kept as
is, anything non-ASCII is replaced by 'u' followed by the hex
encoded unicode value of the character.

Change-Id: I90b0adeb809bc2f6eb4374ce48851396861d4673
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/plugins/coreplugin/corejsextensions.cpp

@@ -142,5 +142,17 @@ QString UtilsJsExtension::mktemp(const QString &pattern) const
     return file.fileName();
 }
 
+QString UtilsJsExtension::asciify(const QString &input) const
+{
+    QString result;
+    for (const QChar c : input) {
+        if (c.isPrint() && c.unicode() < 128)
+            result.append(c);
+        else
+            result.append(QString::fromLatin1("u%1").arg(c.unicode(), 4, 16, QChar('0')));
+    }
+    return result;
+}
+
 } // namespace Internal
 } // namespace Core