[Sheriff] Skip failing test on nacl.

TBR=danno@chromium.org
BUG=v8:2998

Review URL: https://codereview.chromium.org/68163012

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17637 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

test/cctest/cctest.status

@@ -132,5 +132,8 @@
 
   # Fails since 16322 (new test).
   'test-code-stubs-arm/ConvertDToI': [SKIP],
+
+  # BUG(2998).
+  'test-macro-assembler-arm/LoadAndStoreWithRepresentation': [SKIP],
 }],  # 'arch == nacl_ia32 or arch == nacl_x64'
 ]