2348 Add a plugin_platform_interface package (cla: yes)

2349 [video_player_platform_interface] Fix some pedantic lints (cla: yes)

2350 Export SignInOption from interface since it is used in the frontend (cla: yes)

2352 [google_sign_in] Remove unused variable (cla: yes)

2354 [none] Lock pedantic version (cla: yes)

2355 [video_player] Document public API of video_player_platform_interface. (cla: yes, waiting for test harness)

2356 [none] Pass –custom-analysis flag through CI (cla: yes)

2358 adds missing [[ to elif statement in scripts/incremental_build.sh (cla: yes)

2359 [google_sign_in_platform_interface] Add missing docs (cla: yes)