Re enable line numbers through preference

Change-Id: I172dc86d7a19b23e97111751999dde7d601c1d8a
diff --git a/gr-editor/gr-editor.js b/gr-editor/gr-editor.js
index 4621fe7..fc998ca 100644
--- a/gr-editor/gr-editor.js
+++ b/gr-editor/gr-editor.js
@@ -66,8 +66,7 @@
         // TODO(kaspern): Add support for keymaps.
         // params.keyMap = prefs.key_map_type.toLowerCase();
         params.lineLength = prefs.line_length;
-        // Line numbers are currently broken. See Issue 8114.
-        params.lineNumbers = false;
+        params.lineNumbers = prefs.hide_line_numbers;
         params.lineWrapping = prefs.line_wrapping;
         params.indentWithTabs = prefs.indent_with_tabs;
         params.matchBrackets = prefs.match_brackets;