Remove domains from branding forms

We’re deprecating storing the domain as text on a branding in favour of
a database relationship between branding and organisation.

We need to do this now in order to remove the validation on these fields
(which depends on the data in `domains.yml`)

app/templates/views/email-branding/manage-branding.html

@@ -28,7 +28,6 @@
           <div style='margin-top:15px;'>{{textbox(form.name)}}</div>
           <div style='margin-top:15px;'>{{textbox(form.text)}}</div>
           {{ textbox(form.colour, width='1-4', colour_preview=True) }}
-           <div style='margin-top:15px;'>{{textbox(form.domain)}}</div>
            {{ radios(form.brand_type) }}
           {{ page_footer(
             'Save',

app/templates/views/email-branding/select-branding.html

@@ -24,13 +24,6 @@
             {{ brand.name or 'Unnamed' }}
           </a>
         </div>
-        <p class="message-type">
-          {% if brand.domain %}
-            Default for {{ brand.domain }}
-          {% else %}
-            –
-          {% endif %}
-        </p>
       </div>
     {% endfor %}
   </nav>

app/templates/views/letter-branding/manage-letter-branding.html

@@ -25,7 +25,6 @@
       {% call form_wrapper() %}
         <div class="form-group">
           <div style='margin-top:15px;'>{{textbox(letter_branding_details_form.name)}}</div>
-          <div style='margin-top:15px;'>{{textbox(letter_branding_details_form.domain)}}</div>
           {{ page_footer(
             'Save',
             button_name='operation',

app/templates/views/letter-branding/select-letter-branding.html

@@ -24,13 +24,6 @@
             {{ brand.name }}
           </a>
         </div>
-        <p class="message-type">
-          {% if brand.domain %}
-            Default for {{ brand.domain }}
-          {% else %}
-            –
-          {% endif %}
-        </p>
       </div>
     {% endfor %}
   </nav>