This reverts commit ec8693e8.

* c09ef582e [flutter_plugin_tools] Remove UWP (flutter/plugins#5432)

* 3876f54bf [ci.yaml] Remove explicit caches (flutter/plugins#5434)

* 0605d876d [webview_flutter_android] Updates `pigeon` version to support null safety (flutter/plugins#5395)

* 4b687c9fa [video_player] Fix XCUITest based on the new tooltip accessibility label (flutter/plugins#5426)

* e777e515b Roll Flutter from 1b58a593 to 4cea9afc (147 revisions) (flutter/plugins#5437)

* 656e8c443 Roll Flutter from 4cea9afc to 5b713147 (4 revisions) (flutter/plugins#5441)

* f689280bf [flutter_plugin_tools] Validate code blocks in readme-check (flutter/plugins#5436)

* 9c41c6895 Roll Flutter from 5b713147 to 7a742228 (1 revision) (flutter/plugins#5442)

* 160c714e7 Roll Flutter from 7a742228 to 2eed8cbf (1 revision) (flutter/plugins#5443)