No functional changes, this is just a small refactor extracting from a future CL that makes the LSP CodeActions tests (and the supporting mixin) work against the `SharedTestInterface` so that they can be shared between the LSP server and Legacy server tests.
It also removes a redundant implementation of `verifyEdit` so both LSP+Legacy tests can use the same implementation, which required fixing the LspOverLegacy base test class to correctly set the local capabilities to match the default set the legacy server uses if the client doesn't provide any explicitly.
Change-Id: Ie6396a6425205aba9bfdcc3f08f34fdfa215ad92
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/428002
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Reviewed-by: Samuel Rawlins <srawlins@google.com>
Commit-Queue: Brian Wilkerson <brianwilkerson@google.com>
Danny Tuppeny
c9dcebcad2