Addressing comments by auraz and singingwolfboy.

Removed JS check for empty url and default url. In template added
i18n support for several strings.

common/lib/xmodule/xmodule/js/src/lti/lti.js

@@ -37,7 +37,7 @@ window.LTI = (function () {
     //
     // @return    undefined
     function initialize(element) {
-        var form, openInANewPage, formAction;
+        var form, openInANewPage;
 
         // In cms (Studio) the element is already a jQuery object. In lms it is
         // a DOM object.
@@ -47,16 +47,6 @@ window.LTI = (function () {
         element = $(element);
 
         form = element.find('.ltiLaunchForm');
-        formAction = form.attr('action');
-
-        // If action is empty string, or action is the default URL that should
-        // not cause a form submit.
-        if (!formAction || formAction === 'http://www.example.com') {
-
-            // Nothing to do - no valid action provided. Error message will be
-            // displaced in browser (HTML).
-            return;
-        }
 
         // We want a Boolean 'true' or 'false'. First we will retrieve the data
         // attribute, and then we will parse it via native JSON.parse().

lms/templates/lti.html

@@ -34,7 +34,7 @@
     % if open_in_a_new_page:
         <p>
             <span class="description">
-                ${display_name} (External resource)
+                ${display_name} (${_('External resource')})
             </span>
             <a href="#" class='link_lti_new_window'>
                 <i class="icon-external-link"></i>
@@ -51,8 +51,8 @@
     % endif
 % else:
     <h3 class="error_message">
-        Please provide launch_url. Click "Edit", and fill in the
-        required fields.
+        ${_('Please provide launch_url. Click "Edit", and fill in the
+        required fields.')}
     </h3>
 %endif
 </div>