perf: Disable webrtc/pause_play_peerconnections on Windows

Disable webrtc/pause_play_peerconnections on Windows since it is
persistently red.

NOTRY=true
TBR=johnchen@chromium.org

Bug: 1051644
Change-Id: If3f24a9232c10c78992f3fd14bcc82a511925ae5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2054943
Reviewed-by: Sami Kyöstilä <skyostil@chromium.org>
Commit-Queue: Sami Kyöstilä <skyostil@chromium.org>
Auto-Submit: Sami Kyöstilä <skyostil@chromium.org>
Cr-Commit-Position: refs/heads/master@{#741093}

tools/perf/expectations.config

@@ -398,6 +398,9 @@ crbug.com/1036143 [ android-pixel-2 ] v8.browsing_mobile-future/browse:chrome:om
 # Benchmark: v8.runtime_stats.top_25
 crbug.com/954229 [ mac ] v8.runtime_stats.top_25/* [ Skip ]
 
+# Benchmark: webrtc
+crbug.com/1051644 [ win ] webrtc/pause_play_peerconnections [ Skip ]
+
 ##### Perf FYI benchmarks go after here #####
 # Benchmark: loading.desktop_layout_ng
 crbug.com/879833 [ linux ] loading.desktop_layout_ng/Walgreens_cold [ Skip ]