Notify user if cookies can't be created

src/locales/en.json

@@ -24,6 +24,7 @@
   "pad.colorpicker.cancel": "Cancel",
 
   "pad.loading": "Loading...",
+  "pad.nocookie": "Cookie could not be found. Please allow cookies in your browser!",
   "pad.passwordRequired": "You need a password to access this pad",
   "pad.permissionDenied": "You do not have permission to access this pad",
   "pad.wrongPassword": "Your password was wrong",

src/static/css/pad.css

@@ -1086,6 +1086,10 @@ input[type=checkbox] {
   display:none;
 }
 
+#nocookie{
+  display:none;
+}
+
 /* gritter stuff */
 #gritter-notice-wrapper {
   position:fixed;

src/static/js/pad.js

@@ -442,6 +442,16 @@ var pad = {
       if (typeof customStart == "function") customStart();
       getParams();
       handshake();
+
+      // To use etherpad you have to allow cookies.
+      // This will check if the creation of a test-cookie has success.
+      // Otherwise it shows up a message to the user.
+      createCookie("test", "test");
+      if (!readCookie("test"))
+      {
+        $('#loading').hide();
+        $('#nocookie').show();
+      }
     });
   },
   _afterHandshake: function()

src/templates/pad.html

@@ -114,6 +114,9 @@
               <div id="wrongPassword">
                 <p data-l10n-id="pad.wrongPassword">Your password was wrong</p>
               </div>
+              <div id="nocookie">
+                <p data-l10n-id="pad.nocookie">Cookie could not be found. Please allow cookies in your browser!</p>
+              </div>
               <% e.begin_block("loading"); %>
               <p data-l10n-id="pad.loading" id="loading">Loading...</p>
               <% e.end_block(); %>