Gardening: Mark animated-composited-inside-hidden.html flaky

TBR=dstockwell@chromium.org, steveblock@chromium.org
BUG=349552

Review URL: https://codereview.chromium.org/183023015

git-svn-id: svn://svn.chromium.org/blink/trunk@168523 bbb929c8-8fbe-4397-9dbb-9b2b20218538

third_party/WebKit/LayoutTests/TestExpectations

@@ -783,6 +783,8 @@ crbug.com/337735 [ Linux ] compositing/overflow/iframe-scroll-children.html [ Pa
 crbug.com/337735 [ Linux ] virtual/gpu/compositedscrolling/overflow/iframe-scroll-children.html [ Pass Crash ]
 crbug.com/337735 [ Linux ] virtual/softwarecompositing/overflow/iframe-scroll-children.html [ Pass Crash ]
 
+crbug.com/349552 [ Android ] compositing/animation/animated-composited-inside-hidden.html [ Pass Timeout ]
+
 crbug.com/333882 [ Win ] inspector/editor/text-editor-selection-to-search.html [ Pass Failure ]
 crbug.com/333882 [ Win ] inspector/elements/edit-trimmed-attribute-value.html [ Pass Failure ]
 crbug.com/333882 [ Win7 ] inspector/elements/styles/styles-change-node-while-editing.html [ Pass Failure ]