Add Crash expectation to offscreencanvas flaky test.

BUG=674858
TBR=junov@chromium.org
NOTRY=true

Review-Url: https://codereview.chromium.org/2581233002
Cr-Commit-Position: refs/heads/master@{#439140}

third_party/WebKit/LayoutTests/TestExpectations

@@ -2230,8 +2230,8 @@ crbug.com/674468 [ Trusty ] compositing/reflections/nested-reflection-transition
 crbug.com/674720 [ Debug Trusty ] http/tests/loading/preload-img-test.html [ Pass Failure ]
 
 # Added 2016-12-16
-crbug.com/674858 [ Linux ] virtual/threaded/printing/offscreencanvas-2d-printing.html [ Pass Failure ]
-crbug.com/674858 [ Linux ] virtual/threaded/printing/offscreencanvas-webgl-printing.html [ Pass Failure ]
+crbug.com/674858 [ Linux ] virtual/threaded/printing/offscreencanvas-2d-printing.html [ Pass Failure Crash ]
+crbug.com/674858 [ Linux ] virtual/threaded/printing/offscreencanvas-webgl-printing.html [ Pass Failure Crash ]
 crbug.com/674917 http/tests/inspector/search/sources-search-scope-many-projects.html [ Pass Failure ]
 
 # for Skia DEPS roll