* Upgrade everything except matcher.
* Roll matcher (and test)
* Adjust tests that depend on flutter:test directly to depend on a shim
* Require use of package:test shim and remove other references to package:test
* Revert "Revert "Move mockito to 3.0.0-alpha. (#15949)" (#15979)"
This reverts commit e59651f925917ed44a9bf27c37e80fc9992c0890.
* More thenReturn to thenAnswer when mocking Futures
* Revert "More thenReturn to thenAnswer when mocking Futures"
This reverts commit 194d2cf41754ad171efd6bb5898cf73bce5a75ab as we are reverting engine roll.
* Revert "Revert "More thenReturn to thenAnswer when mocking Futures""
This reverts commit 52c9e96b304b220f66d78a252fccea0c8e0ef24c.
* Add dependency override
* Fix issue
* Move mockito to 3.0.0-alpha.
This is needed so it matches mockito version used internally.
* Pick up +2 for the fixes
* Fix whenReturn in fuchsia_remote_debug_protocol
* more thenReturn becomes thenAnswer
* more thenReturn becomes thenAnswer
* more thenReturn becomes thenAnswer
* Remove the workaround that pinned args to v0.13.6
This reverts most of the changes in commit 6331b6c8b5d964ec0dbf2cd9bb84c60c650a0878
* throw exception if exit code is not an integer
* rework command infrastructure to throw ToolExit when non-zero exitCode
* convert commands to return Future<Null>
* cleanup remaining commands to use throwToolExit for non-zero exit code
* remove isUnusual exception message
* add type annotations for updated args package
