Fix an issue with {M13} and Spaces

Fixes T8529. These elements now need a viewer/object to render Spaces.

Auditors: btrahan

src/applications/pholio/remarkup/PholioRemarkupRule.php

@@ -64,7 +64,10 @@ final class PholioRemarkupRule extends PhabricatorObjectRemarkupRule {
     PhabricatorObjectHandle $handle,
     $options) {
 
+    $viewer = $this->getEngine()->getConfig('viewer');
+
     $embed_mock = id(new PholioMockEmbedView())
+      ->setUser($viewer)
       ->setMock($object);
 
     if (strlen($options)) {

src/applications/pholio/view/PholioMockEmbedView.php

@@ -47,6 +47,8 @@ final class PholioMockEmbedView extends AphrontView {
     list($x, $y) = $xform->getTransformedDimensions($thumbfile);
 
     $item = id(new PHUIPinboardItemView())
+      ->setUser($this->getUser())
+      ->setObject($mock)
       ->setHeader($header)
       ->setURI($uri)
       ->setImageURI($thumbnail)