3545 Honor, and scrub, the 1.0 compatibility promise (cla: yes, p: android_intent, p: connectivity, p: device_info, p: package_info, p: path_provider, p: sensors, p: share, p: shared_preferences, p: url_launcher, p: video_player, platform-linux, platform-macos, platform-web, platform-windows)

3546 [video_player] Update video_player readme to change sample video to https (cla: yes, documentation, p: video_player)

3561 [video_player] Ignore setting mixWithOthers in web (cla: yes, p: video_player, platform-web)

3574 [video_player_web] Bump version for NNBD stable (cla: yes, nnbd, p: video_player, platform-web)