Fix several issues with Differential exception email

Summary:
  - Assigning $cc_phids clobbers the correct value assigned on line 80.
  - Remove stack trace noise, the trace is always meaningless and well-known.
  - Actually show the original body.

Test Plan: Piped mail to the mail receiver and verified the errors didn't CC revision CCs, no longer had traces, and included the original raw text body.

Reviewers: btrahan, jungejason

Reviewed By: jungejason

CC: aran

Differential Revision: https://secure.phabricator.com/D2969

src/applications/differential/DifferentialReplyHandler.php

@@ -162,7 +162,7 @@ class DifferentialReplyHandler extends PhabricatorMailReplyHandler {
       $exception_mail = new DifferentialExceptionMail(
         $this->getMailReceiver(),
         $ex,
-        $body);
+        $this->receivedMail->getRawTextBody());
 
       $exception_mail->setToPHIDs(array($this->getActor()->getPHID()));
       $exception_mail->send();

src/applications/differential/mail/DifferentialExceptionMail.php

@@ -45,16 +45,13 @@ final class DifferentialExceptionMail extends DifferentialMail {
     $original_body = $this->originalBody;
 
     $message = $exception->getMessage();
-    $trace   = $exception->getTraceAsString();
 
     return <<<EOBODY
 Your request failed because an exception was encoutered while processing it:
 
 EXCEPTION: {$message}
 
-{$trace}
-
--- Original Body --------------------------
+-- Original Body -------------------------------------------------------------
 
 {$original_body}
 

src/applications/differential/mail/DifferentialMail.php

@@ -124,7 +124,6 @@ abstract class DifferentialMail {
           '<'.implode('>, <', $reviewer_phids).'>');
       }
 
-      $cc_phids = $revision->getCCPHIDs();
       if ($cc_phids) {
         $template->addPHIDHeaders('X-Differential-CC', $cc_phids);
         $template->addHeader(

src/applications/metamta/storage/PhabricatorMetaMTAReceivedMail.php

@@ -222,6 +222,10 @@ final class PhabricatorMetaMTAReceivedMail extends PhabricatorMetaMTADAO {
     return $parser->stripTextBody($body);
   }
 
+  public function getRawTextBody() {
+    return idx($this->bodies, 'text');
+  }
+
   public static function loadReceiverObject($receiver_name) {
     if (!$receiver_name) {
       return null;