This reverts commit 027d4eca.

Revert "[flutter_tools] remove mocks, globals from golden comparator and test runner tests (#81423)" (#81487)

This reverts commit 8fe4cc79.

This reverts commit 8b6baae4.

Our current top crasher is an unclear error when ProcessManager fails to resolve an executable path. To fix this, we'd like to being adjusting the process resolution logic and adding more instrumentation to track failures. In order to begin the process, the ProcessManager has been folded back into the flutter tool

* opt out the flutter tool

* oops EOF

* fix import

* Update tool_backend.dart

* Update daemon_client.dart

* fix more

Last batch of test fixes for general shard.