[ci] Re-enable pathified unit tests (flutter#3268)

* [ci] Re-enable pathified unit tests

Long-term, this should be fixed when we migrate Linux to LUCI since we
can extend the timeout to cover pathalogical cases. For the
short-to-medium term, I'm hoping we'll be fine since the PR that
triggered this was very close to being the worst case we could have
constructed, and it still almost made it within an hour.

* Indentation fix

.cirrus.yml

@@ -243,13 +243,12 @@ task:
           CHANNEL: "stable"
       unit_test_script:
         - ./script/tool_runner.sh test --exclude=script/configs/dart_unit_tests_exceptions.yaml
-        # TODO(stuartmorgan): Re-enable once https://github.com/flutter/packages/pull/3256 lands.
-        #pathified_unit_test_script:
+      pathified_unit_test_script:
         # Run tests with path-based dependencies to ensure that publishing
         # the changes won't break tests of other packages in the repository
         # that depend on it.
-        #- ./script/tool_runner.sh make-deps-path-based --target-dependencies-with-non-breaking-updates
-        #- $PLUGIN_TOOL_COMMAND test --run-on-dirty-packages --exclude=script/configs/dart_unit_tests_exceptions.yaml
+        - ./script/tool_runner.sh make-deps-path-based --target-dependencies-with-non-breaking-updates
+        - $PLUGIN_TOOL_COMMAND test --run-on-dirty-packages --exclude=script/configs/dart_unit_tests_exceptions.yaml
     - name: linux-custom_package_tests
       env:
         PATH: $PATH:/usr/local/bin