Skip v8.detached_context_age_in_gc on all platforms.

It is failing all test cases on all platforms.

Bug: 809063
Change-Id: I64f09cc842edb6e1541508067b9b9babcc82a3e4
Tbr: nednguyen@google.com
Reviewed-on: https://chromium-review.googlesource.com/901903Reviewed-by: Annie Sullivan <sullivan@chromium.org>
Reviewed-by: Charlie Andrews <charliea@chromium.org>
Commit-Queue: Annie Sullivan <sullivan@chromium.org>
Cr-Commit-Position: refs/heads/master@{#534444}

tools/perf/expectations.config

@@ -350,6 +350,7 @@ crbug.com/803465 [ Nexus_5 ] v8.browsing_mobile-future/browse:chrome:newtab [ Sk
 
 # Benchmark: v8.detached_context_age_in_gc
 crbug.com/770982 [ Win ] v8.detached_context_age_in_gc/Docs_(1_open_document_tab) [ Skip ]
+crbug.com/809063 [ All ] v8.detached_context_age_in_gc/* [ Skip ]
 
 # Benchmark: v8.runtime_stats.top_25
 crbug.com/664318 [ Android ] v8.runtime_stats.top_25/* [ Skip ]