This removes all telemetry which expired in Firefox 69 or earlier, with the
exceptions of the following, which we plan to renew:
* AUDIO_TRACK_SILENCE_PROPORTION
* MEDIA_AUTOPLAY_WOULD_BE_ALLOWED_COUNT
* MEDIA_AUTOPLAY_WOULD_NOT_BE_ALLOWED_COUNT
* MEDIACACHESTREAM_LENGTH_KB
* MEDIA_MKV_CANPLAY_REQUESTED
* MEDIA_PAGE_COUNT
* MEDIA_PAGE_HAD_MEDIA_COUNT
* VIDEO_DROPPED_FRAMES_PROPORTION
* VIDEO_PLAY_TIME
* VIDEO_HIDDEN_PLAY_TIME
* VIDEO_HIDDEN_PLAY_TIME_PERCENTAGE
* VIDEO_INFERRED_DECODE_SUSPEND_PERCENTAGE
* VIDEO_INTER_KEYFRAME_AVERAGE_MS
* VIDEO_INTER_KEYFRAME_MAX_MS
* VIDEO_SUSPEND_RECOVERY_TIME_MS
* VIDEO_VP9_BENCHMARK_FPS
* WEB_AUDIO_BECOMES_AUDIBLE_TIME
* WEBVTT_TRACK_KINDS

Differential Revision: https://phabricator.services.mozilla.com/D37313

--HG--
extra : moz-landing-system : lando