Disabling dummy_benchmark.stable_benchmark_1/dummy_page.html on win

TBR=charliea@chromium.org
NOTRY=true

Bug: 848900
Change-Id: I8fa3a3cad3515ec16ba19f558875be13910c902b
Reviewed-on: https://chromium-review.googlesource.com/1100960Reviewed-by: Emily Hanley <eyaich@chromium.org>
Commit-Queue: Emily Hanley <eyaich@chromium.org>
Cr-Commit-Position: refs/heads/master@{#567251}

tools/perf/expectations.config

@@ -54,6 +54,7 @@ crbug.com/844541 [ Android_One ] dromaeo/http://dromaeo.com?dom-modify [ Skip ]
 #
 # Benchmark: dummy_benchmark
 crbug.com/848900 [ Win ] dummy_benchmark.histogram_benchmark_1/dummy_page.html [ Skip ]
+crbug.com/848900 [ Win ] dummy_benchmark.stable_benchmark_1/dummy_page.html [ Skip ]
 
 # Benchmark: blink_perf.svg
 crbug.com/736817 [ Nexus_5X ] blink_perf.svg/SvgCubics.html [ Skip ]