Removing transitive dependencies from flutter_test

[Jonah Williams]

Howdy,

As part of an ongoing effort to reduce versioning friction and make it easier to upgrade flutter versions, I've landed a recent change in master that drastically shrinks the set of transitive dependencies of flutter_test.

The set of removed packages include:

analyzer

args

convert
crypto
csslib

[Jonah Williams]

(Woops, I was not finished typing. Oh well continuing:)

front_end
glob
html
http http_multi_server http_parser io js json_rpc_2 kernel logging mime multi_server_socket node_preamble package_config package_resolver plugin pool pub_semver shelf shelf_packages_handler shelf_static shelf_web_socket source_map_stack_trace source_maps test utf vm_service_client watcher web_socket_channel yaml
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If you are using any of these dependencies, they will need to be explicitly added to your pubspec.yaml.

Additionally, the newest flutter_test requires test `^1.5.1` and mockito `^4.0.0`. There have been no breaking changes between these and older versions.

If you have any comments or questions, please let me know!

Thanks!