Fix an issue with embedding slowvotes

Summary:
In some applications, using `{V2}` syntax to embed a vote throws. The chain of causality looks like this:

  - We try to render a `phabricator_form()`.
  - This requires a CSRF token.
  - We look for a CSRF token on the user.
  - It's an omnipotent user with no token, so everything fails.

To resolve this, make sure we always pass the real user in.

Test Plan:
  - Lots of `grep`.
  - Made a Differential comment with `{V2}`.
  - Made a Diffusion comment with `{V2}`.
  - Made a Maniphest comment with `{V2}`.
  - Replied to a Conpherence thread with `{V2}`.
  - Created a Conpherence thread with `{V2}`.
  - Used Conduit to update a Conpherence thread with `{V2}`.

Reviewers: btrahan

Reviewed By: btrahan

Subscribers: epriestley, lkassianik

Differential Revision: https://secure.phabricator.com/D8849

src/applications/audit/editor/PhabricatorAuditCommentEditor.php

@@ -76,6 +76,7 @@ final class PhabricatorAuditCommentEditor extends PhabricatorEditor {
 
     // Find any "@mentions" in the content blocks.
     $mention_ccs = PhabricatorMarkupEngine::extractPHIDsFromMentions(
+      $this->getActor(),
       $content_blocks);
     if ($mention_ccs) {
       $metacc = idx(

src/applications/conpherence/conduit/ConduitAPI_conpherence_updatethread_Method.php

@@ -90,7 +90,10 @@ final class ConduitAPI_conpherence_updatethread_Method
     if ($message) {
       $xactions = array_merge(
         $xactions,
-        $editor->generateTransactionsFromText($conpherence, $message));
+        $editor->generateTransactionsFromText(
+          $user,
+          $conpherence,
+          $message));
     }
 
     try {

src/applications/conpherence/controller/ConpherenceUpdateController.php

@@ -55,6 +55,7 @@ final class ConpherenceUpdateController
         case ConpherenceUpdateActions::MESSAGE:
           $message = $request->getStr('text');
           $xactions = $editor->generateTransactionsFromText(
+            $user,
             $conpherence,
             $message);
           $delete_draft = true;

src/applications/conpherence/editor/ConpherenceEditor.php

@@ -34,9 +34,9 @@ final class ConpherenceEditor extends PhabricatorApplicationTransactionEditor {
       $errors[] = self::ERROR_EMPTY_MESSAGE;
     }
 
-    $file_phids =
-      PhabricatorMarkupEngine::extractFilePHIDsFromEmbeddedFiles(
-        array($message));
+    $file_phids = PhabricatorMarkupEngine::extractFilePHIDsFromEmbeddedFiles(
+      $creator,
+      array($message));
     if ($file_phids) {
       $files = id(new PhabricatorFileQuery())
         ->setViewer($creator)
@@ -78,13 +78,14 @@ final class ConpherenceEditor extends PhabricatorApplicationTransactionEditor {
   }
 
   public function generateTransactionsFromText(
+    PhabricatorUser $viewer,
     ConpherenceThread $conpherence,
     $text) {
 
     $files = array();
-    $file_phids =
-      PhabricatorMarkupEngine::extractFilePHIDsFromEmbeddedFiles(
-        array($text));
+    $file_phids = PhabricatorMarkupEngine::extractFilePHIDsFromEmbeddedFiles(
+      $viewer,
+      array($text));
     // Since these are extracted from text, we might be re-including the
     // same file -- e.g. a mock under discussion. Filter files we
     // already have.

src/applications/conpherence/mail/ConpherenceReplyHandler.php

@@ -82,6 +82,7 @@ final class ConpherenceReplyHandler extends PhabricatorMailReplyHandler {
     $xactions = array_merge(
       $xactions,
       $editor->generateTransactionsFromText(
+        $user,
         $conpherence,
         $body));
 

src/applications/maniphest/controller/ManiphestTransactionSaveController.php

@@ -26,6 +26,7 @@ final class ManiphestTransactionSaveController extends ManiphestController {
     // list of all the CCs and then construct a transaction for them at the
     // end if necessary.
     $added_ccs = PhabricatorMarkupEngine::extractPHIDsFromMentions(
+      $user,
       array(
         $request->getStr('comments'),
       ));

src/applications/transactions/editor/PhabricatorApplicationTransactionEditor.php

@@ -973,7 +973,9 @@ abstract class PhabricatorApplicationTransactionEditor
     }
 
     $texts = array_mergev($blocks);
-    $phids = PhabricatorMarkupEngine::extractPHIDsFromMentions($texts);
+    $phids = PhabricatorMarkupEngine::extractPHIDsFromMentions(
+      $this->getActor(),
+      $texts);
 
     $this->mentionedPHIDs = $phids;
 
@@ -2173,6 +2175,7 @@ abstract class PhabricatorApplicationTransactionEditor
     $phids = array();
     if ($blocks) {
       $phids[] = PhabricatorMarkupEngine::extractFilePHIDsFromEmbeddedFiles(
+        $this->getActor(),
         $blocks);
     }
 

src/infrastructure/markup/PhabricatorMarkupEngine.php

@@ -494,11 +494,14 @@ final class PhabricatorMarkupEngine {
     return $engine;
   }
 
-  public static function extractPHIDsFromMentions(array $content_blocks) {
+  public static function extractPHIDsFromMentions(
+    PhabricatorUser $viewer,
+    array $content_blocks) {
+
     $mentions = array();
 
     $engine = self::newDifferentialMarkupEngine();
-    $engine->setConfig('viewer', PhabricatorUser::getOmnipotentUser());
+    $engine->setConfig('viewer', $viewer);
 
     foreach ($content_blocks as $content_block) {
       $engine->markupText($content_block);
@@ -512,11 +515,12 @@ final class PhabricatorMarkupEngine {
   }
 
   public static function extractFilePHIDsFromEmbeddedFiles(
+    PhabricatorUser $viewer,
     array $content_blocks) {
     $files = array();
 
     $engine = self::newDifferentialMarkupEngine();
-    $engine->setConfig('viewer', PhabricatorUser::getOmnipotentUser());
+    $engine->setConfig('viewer', $viewer);
 
     foreach ($content_blocks as $content_block) {
       $engine->markupText($content_block);