[Minor] WebUI: Use public getSelector() function

interface/js/app/config.js

         ui.setup = function (rspamd) {
         // Modal form for maps
             $(document).on("click", "[data-toggle=\"modal\"]", function () {
-                function getSelector(id) {
-                    var e = document.getElementById(id);
-                    return e.options[e.selectedIndex].value;
-                }
-                var checked_server = getSelector("selSrv");
+                var checked_server = rspamd.getSelector("selSrv");
                 var item = $(this).data("item");
                 rspamd.query("getmap", {
                     headers: {

interface/js/app/graph.js

             }
         };
 
-        // Get selectors' current state
-        function getSelector(id) {
-            var e = document.getElementById(id);
-            return e.options[e.selectedIndex].value;
-        }
-
-        function initGraph() {
+        function initGraph(rspamd) {
             var graph = new D3Evolution("graph", $.extend({}, graph_options, {
-                yScale: getSelector("selYScale"),
-                type: getSelector("selType"),
-                interpolate: getSelector("selInterpolate"),
-                convert: getSelector("selConvert"),
+                yScale: rspamd.getSelector("selYScale"),
+                type: rspamd.getSelector("selType"),
+                interpolate: rspamd.getSelector("selInterpolate"),
+                convert: rspamd.getSelector("selConvert"),
             }));
             $("#selYScale").change(function () {
                 graph.yScale(this.value);
             }
 
             if (!graphs.graph) {
-                graphs.graph = initGraph();
+                graphs.graph = initGraph(rspamd);
             }
 
             rspamd.query("graph", {
             });
         };
 
-        ui.setup = function () {
+        ui.setup = function (rspamd) {
             // Handling mouse events on overlapping elements
             $("#rrd-pie").mouseover(function () {
                 $("#rrd-pie").css("z-index", "200");
                 $("#rrd-table_toggle").css("z-index", "0");
             });
 
-            return getSelector("selData");
+            return rspamd.getSelector("selData");
         };
 
         return ui;

interface/js/app/rspamd.js

         return sessionStorage.getItem("Password");
     }
 
+    // Get selectors' current state
     function getSelector(id) {
         var e = document.getElementById(id);
         return e.options[e.selectedIndex].value;
         tab_history.setup(ui, tables);
         tab_symbols.setup(ui, tables);
         tab_upload.setup(ui, tables);
-        selData = tab_graph.setup();
+        selData = tab_graph.setup(ui);
     };
 
     ui.connect = function () {

interface/js/app/symbols.js

         "use strict";
         var ui = {};
 
-        function getSelector(id) {
-            var e = document.getElementById(id);
-            return e.options[e.selectedIndex].value;
-        }
-
         function saveSymbols(rspamd, action, id, server) {
             var inputs = $("#" + id + " :input[data-role=\"numerictextbox\"]");
             var url = action;
             var digits = Number(number).toFixed(20).replace(/^-?\d*\.?|0+$/g, "").length;
             return (digits === 0 || digits > 4) ? 0.1 : 1.0 / Math.pow(10, digits);
         }
-        function process_symbols_data(data) {
+        function process_symbols_data(rspamd, data) {
             var items = [];
             var lookup = {};
             var freqs = [];
             var distinct_groups = [];
-            var selected_server = getSelector("selSrv");
+            var selected_server = rspamd.getSelector("selSrv");
 
             data.forEach(function (group) {
                 group.rules.forEach(function (item) {
             rspamd.query("symbols", {
                 success: function (json) {
                     var data = json[0].data;
-                    var items = process_symbols_data(data);
+                    var items = process_symbols_data(rspamd, data);
 
                     /* eslint-disable consistent-this, no-underscore-dangle, one-var-declaration-per-line */
                     FooTable.groupFilter = FooTable.Filtering.extend({
         ui.setup = function (rspamd, tables) {
             $("#updateSymbols").on("click", function (e) {
                 e.preventDefault();
-                var checked_server = getSelector("selSrv");
+                var checked_server = rspamd.getSelector("selSrv");
                 rspamd.query("symbols", {
                     success: function (data) {
-                        var items = process_symbols_data(data[0].data)[0];
+                        var items = process_symbols_data(rspamd, data[0].data)[0];
                         tables.symbols.rows.load(items);
                     },
                     server: (checked_server === "All SERVERS") ? "local" : checked_server