[System Health] Create first System Health media user stories.

tools/perf/page_sets/data/system_health_desktop.json

Index: tools/perf/page_sets/data/system_health_desktop.json
diff --git a/tools/perf/page_sets/data/system_health_desktop.json b/tools/perf/page_sets/data/system_health_desktop.json
index 5364741ec5ebea766933ccd46a7c8ef4571a5cfc..f6e1f57fd62a3e66fa2925e703a65fa5c6b01be7 100644
--- a/tools/perf/page_sets/data/system_health_desktop.json
+++ b/tools/perf/page_sets/data/system_health_desktop.json
@@ -97,9 +97,13 @@
             "browse:media:youtube"
         ],
         "system_health_desktop_028.wpr": [
-             "long_running:tools:gmail-foreground",
-             "long_running:tools:gmail-background"
+            "long_running:tools:gmail-foreground",
+            "long_running:tools:gmail-background"
+        ],
+        "system_health_desktop_030.wpr": [
+            "media:audio:soundcloud",
+            "media:audio:google_play_music"
         ]
     },
     "description": "Describes the Web Page Replay archives for a story set. Don't edit by hand! Use record_wpr for updating."
-}
+}