Provide getter for test results properties in arc diff

Summary: We want to use them in event.

Test Plan: Will use it in event.

Reviewers: epriestley

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D3690

src/workflow/ArcanistDiffWorkflow.php

@@ -1371,6 +1371,10 @@ EOTEXT
     return null;
   }
 
+  public function getTestResults() {
+    return $this->testResults;
+  }
+
   private function getErrorExcuse($prompt, $history) {
     if ($this->getArgument('excuse')) {
       $prompt .= " Ignore them?";