Fix antiproxying config options.

Don't embed config options directly in Javascript. Including them in the
Javascript forces us to recompile the Javascript whenever these options
change, which requires us to redeploy the entire site instead of just
restarting the app server.

app/javascript/src/javascripts/common.js

@@ -0,0 +1,30 @@
+import Cookie from './cookie'
+
+$(function() {
+  $("#hide-upgrade-account-notice").on("click.danbooru", function(e) {
+    $("#upgrade-account-notice").hide();
+    Cookie.put('hide_upgrade_account_notice', '1', 7);
+    e.preventDefault();
+  });
+
+  $("#hide-dmail-notice").on("click.danbooru", function(e) {
+    var $dmail_notice = $("#dmail-notice");
+    $dmail_notice.hide();
+    var dmail_id = $dmail_notice.data("id");
+    Cookie.put("hide_dmail_notice", dmail_id);
+    e.preventDefault();
+  });
+
+  $("#close-notice-link").on("click.danbooru", function(e) {
+    $('#notice').fadeOut("fast");
+    e.preventDefault();
+  });
+
+  if (Danbooru.config["enable_antiproxying?"] && !location.hostname.endsWith(Danbooru.config.domain)) {
+    location.hostname = Danbooru.config.hostname;
+  }
+});
+
+window.submitInvisibleRecaptchaForm = function () {
+  document.getElementById("signup-form").submit();
+}