Update TestExpectations for restart-not-visible

The flakiness dashboard for
virtual/threaded/animations/restart-not-visible.html
shows that the test is currently timing out on debug builds and
passing everywhere else. This patch updates the entry for this test
in TestExpectations to be more specific.

BUG=567230

Review-Url: https://codereview.chromium.org/2022093003
Cr-Commit-Position: refs/heads/master@{#397091}

third_party/WebKit/LayoutTests/TestExpectations

@@ -1136,7 +1136,7 @@ crbug.com/525296 fast/css/font-load-while-styleresolver-missing.html [ Crash Fai
 crbug.com/240576 fullscreen/api/element-ready-check-containing-iframe.html [ Timeout Failure Pass ]
 crbug.com/240576 virtual/android/fullscreen/api/element-ready-check-containing-iframe.html [ Timeout Failure Pass ]
 
-crbug.com/567230 virtual/threaded/animations/restart-not-visible.html [ Timeout Crash Pass ]
+crbug.com/567230 [ Debug ] virtual/threaded/animations/restart-not-visible.html [ Timeout ]
 
 crbug.com/567419 inspector/elements/styles-2/metrics-box-sizing.html [ Skip ]