[Speed docs] Add media harness documentation.

R=johnchen@chromium.org, kxloh@chromium.org

Change-Id: I9b50043385af5fb93f19a6d1c4c7244754486591
bug: 853749, 949246
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1765443Reviewed-by: John Chen <johnchen@chromium.org>
Commit-Queue: Caleb Rouleau <crouleau@chromium.org>
Auto-Submit: Caleb Rouleau <crouleau@chromium.org>
Cr-Commit-Position: refs/heads/master@{#690025}

docs/speed/benchmark/harnesses/media.md

+# Media Benchmarks
+
+There is no detailed external version of the documentation for media Telemetry harness.
+
+Googlers can find the internal documentation here: http://go/videostack-chromeperf-sheriff
+
+## Overview
+
+The media benchmarking harness consists of the
+[media story set](../../../../tools/perf/page_sets/media_cases.py),
+and the [media
+metric](https://chromium.googlesource.com/catapult.git/+/HEAD/tracing/tracing/metrics/media_metric.html).
+Those two elements are brought together by the
+[media benchmark](../../../../tools/perf/benchmarks/media.py).
+
+The media story set is a set webpages along with
+instructions for automating interactions with them. The media story set consists
+of two types of stories: src= stories and MSE stories. The src= stories simply
+run a saved media file from start to end. The MSE stories directly call various
+MSE APIs.
+
+The media metric takes in a trace file and computes various metrics such as
+seek time and time to play using the trace events.

tools/perf/benchmark.csv

@@ -28,8 +28,8 @@ kraken,hablich@chromium.org,Blink>JavaScript,,
 load_library_perf_tests,"xhwang@chromium.org, crouleau@chromium.org",Internals>Media>Encrypted,,
 loading.desktop,"kouhei@chromium.org, ksakamoto@chromium.org",Blink>Loader,https://bit.ly/loading-benchmarks,"cache_temperature_cold,cache_temperature_warm,international,intl_ar_fa_he,intl_es_fr_pt_BR,intl_hi_ru,intl_ja_zh,intl_ko_th_vi,typical"
 loading.mobile,"kouhei@chromium.org, ksakamoto@chromium.org",Blink>Loader,https://bit.ly/loading-benchmarks,"cache_temperature_cold,cache_temperature_hot,cache_temperature_warm,easy_ttfmp,easy_tti,global,pwa,tough_ttfmp,tough_tti"
-media.desktop,dalecurtis@chromium.org,Internals>Media,,"aac,audio_only,audio_video,av1,background,beginning_to_end,busyjs,cns,h264,is_4k,is_50fps,mp3,mse,opus,seek,src,video_only,vorbis,vp8,vp9"
-media.mobile,dalecurtis@chromium.org,Internals>Media,,"aac,audio_only,audio_video,background,beginning_to_end,busyjs,cns,h264,mp3,mse,opus,seek,src,video_only,vorbis,vp9"
+media.desktop,dalecurtis@chromium.org,Internals>Media,https://chromium.googlesource.com/chromium/src/+/master/docs/speed/benchmark/harnesses/media.md,"aac,audio_only,audio_video,av1,background,beginning_to_end,busyjs,cns,h264,is_4k,is_50fps,mp3,mse,opus,seek,src,video_only,vorbis,vp8,vp9"
+media.mobile,dalecurtis@chromium.org,Internals>Media,https://chromium.googlesource.com/chromium/src/+/master/docs/speed/benchmark/harnesses/media.md,"aac,audio_only,audio_video,background,beginning_to_end,busyjs,cns,h264,mp3,mse,opus,seek,src,video_only,vorbis,vp9"
 media_perftests,"crouleau@chromium.org, dalecurtis@chromium.org",Internals>Media,,
 memory.desktop,erikchen@chromium.org,,,
 net_perftests,net-dev@chromium.org,Internals>Network,,

tools/perf/benchmarks/media.py

@@ -45,7 +45,8 @@ class _MediaBenchmark(perf_benchmark.PerfBenchmark):
 
 
 @benchmark.Info(emails=['dalecurtis@chromium.org'],
-                component='Internals>Media')
+                component='Internals>Media',
+                documentation_url='https://chromium.googlesource.com/chromium/src/+/master/docs/speed/benchmark/harnesses/media.md')  # pylint: disable=line-too-long
 class MediaDesktop(_MediaBenchmark):
   """Obtains media performance for key user scenarios on desktop."""
   SUPPORTED_PLATFORMS = [story.expectations.ALL_DESKTOP]
@@ -60,7 +61,8 @@ class MediaDesktop(_MediaBenchmark):
 
 # If any story is failing on svelte, please only disable on svelte.
 @benchmark.Info(emails=['dalecurtis@chromium.org'],
-                component='Internals>Media')
+                component='Internals>Media',
+                documentation_url='https://chromium.googlesource.com/chromium/src/+/master/docs/speed/benchmark/harnesses/media.md')  # pylint: disable=line-too-long
 class MediaMobile(_MediaBenchmark):
   """Obtains media performance for key user scenarios on mobile devices."""
 

tools/perf/core/undocumented_benchmarks.py

@@ -15,8 +15,6 @@ UNDOCUMENTED_BENCHMARKS = {
   'jetstream',
   'kraken',
   'load_library_perf_tests',
-  'media.desktop',
-  'media.mobile',
   'media_perftests',
   'memory.desktop',
   'net_perftests',