[media telemetry] Use WIFI CNS instead of 3G CNS to fix timeout issue.

This also shortens test length, which is always nice.

Bug: 859660
Change-Id: I83ec61d85b7629ebaa74514adddacc29a767535d
Reviewed-on: https://chromium-review.googlesource.com/c/1341001Reviewed-by: John Chen <johnchen@chromium.org>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Commit-Queue: Caleb Rouleau <crouleau@chromium.org>
Cr-Commit-Position: refs/heads/master@{#609051}

tools/perf/expectations.config

@@ -302,12 +302,6 @@ crbug.com/892704 [ Android_Webview ] system_health.memory_mobile/browse:tech:dis
 crbug.com/747026 [ Mac ] tab_switching.typical_25/multitab:misc:typical24 [ Skip ]
 crbug.com/883731 [ Win ] tab_switching.typical_25/multitab:misc:typical24 [ Skip ]
 
-# Benchmark: media.desktop
-crbug.com/859660 [ All ] media.desktop/video.html?src=tulip2.vp9.webm_Regular-3G [ Skip ]
-
-# Benchmark: media.mobile
-crbug.com/859175 [ Android ] media.mobile/video.html?src=tulip2.vp9.webm_Regular-3G [ Skip ]
-
 # Benchmark: v8.browsing_desktop
 crbug.com/773084 [ Mac ] v8.browsing_desktop/browse:tools:maps [ Skip ]
 crbug.com/788796 [ Linux ] v8.browsing_desktop/browse:media:imgur [ Skip ]

tools/perf/page_sets/media_cases.py

@@ -257,7 +257,7 @@ class MediaCasesStorySet(story.StorySet):
             url=_URL_BASE + 'video.html?src=tulip2.vp9.webm',
             page_set=self,
             tags=['vp9', 'opus', 'audio_video'],
-            traffic_setting=traffic_setting_module.REGULAR_3G),
+            traffic_setting=traffic_setting_module.WIFI),
         _BeginningToEndPlayPage(
             url=_URL_BASE + 'video.html?src=tulip2.vp9.webm',
             page_set=self,