3972 Clean up cruft in pubspec.yaml files (cla: yes, p: battery, p: camera, p: google_maps_flutter, p: google_sign_in, p: image_picker, p: in_app_purchase, p: plugin_platform_interface, p: url_launcher, p: shared_preferences, p: sensors, platform-windows, platform-web)

3973 [scripts/tool] use ‘flutter pub get’ for both dart and flutter packages (cla: yes)

3975 [video_player] Update README.md (cla: yes, waiting for tree to go green, p: video_player)

3976 [in_app_purchase] Revert changes from PR 3897 (cla: yes, p: in_app_purchase, platform-ios)