MDL-65059 messaging: don't refer to block plugin type

AMOS BEGIN
 CPY [block,core],[blockuserconfirmbutton,core_message]
AMOS END

lang/en/message.php

@@ -36,6 +36,7 @@ $string['blockcontact'] = 'Block contact';
 $string['blockedusers'] = 'Blocked users';
 $string['blockuser'] = 'Block user';
 $string['blockuserconfirm'] = 'Are you sure you want to block {$a}?';
+$string['blockuserconfirmbutton'] = 'Block';
 $string['blocknoncontacts'] = 'Prevent non-contacts from messaging me';
 $string['canceledit'] = 'Cancel editing messages';
 $string['contactableprivacy'] = 'Accept messages from:';

message/templates/message_drawer_view_conversation_body_confirm_dialogue.mustache

@@ -39,7 +39,7 @@
     <h3 class="h6 hidden" data-region="dialogue-header"></h3>
     <p class="text-muted" data-region="dialogue-text"></p>
     <button type="button" class="btn btn-primary btn-block hidden" data-action="confirm-block">
-        <span data-region="dialogue-button-text">{{#str}} block, core {{/str}}</span>
+        <span data-region="dialogue-button-text">{{#str}} blockuserconfirmbutton, core_message {{/str}}</span>
         <span class="hidden" data-region="loading-icon-container">{{> core/loading }}</span>
     </button>
     <button type="button" class="btn btn-primary btn-block hidden" data-action="confirm-unblock">