Avoid CSP issues with OpenID login

To avoid Chrom getting upset about sending form data to sites
that our policy doesn't allow, even when it isn't, use Javascript
to jump straight to Omniauth as the direct OpenID based login
buttons were already doing.

Fixes #1909

app/views/users/login.html.erb

@@ -40,6 +40,13 @@
         <%= submit_tag t('.login_button'), :tabindex => 4 %>
       </fieldset>
 
+    </div>
+
+  <% end %>
+
+  <%= form_tag(auth_path(:provider => "openid"), { :id => "openid_login_form" }) do %>
+    <div id="loginForm" class="standard-form">
+
       <fieldset class='form-divider'>
 
         <p class='standard-label'><%= t '.with external' %></p>
@@ -68,15 +75,11 @@
 
         <div id='login_openid_url' class='form-row'>
           <label for='openid_url' class="standard-label"><%= raw t '.openid', :logo => openid_logo %></label>
+          <%= hidden_field_tag("openid_referer", params[:referer]) if params[:referer] %>
           <%= text_field_tag("openid_url", "", { :tabindex => 3, :class => "openid_url" }) %>
           <span class="minorNote">(<a href="<%= t 'users.account.openid.link' %>" target="_new"><%= t 'users.account.openid.link text' %></a>)</span>
         </div>
 
-        <div class='form-row'>
-          <%= check_box_tag "remember_me_openid", "yes", false, :tabindex => 5 %>
-          <label class="standard-label" for="remember_me_openid"><%= t '.remember' %></label>
-        </div>
-
         <%= submit_tag t('.login_button'), :tabindex => 6, :id => "login_openid_submit" %>
 
       </fieldset>