This reverts commit 7cdc23b3e1bae2bc7bc2d1f34773eaa3629d4fcc.
The failure in the `native_assets_test` integration test on Windows was caused by the DevTools process not being shutdown by the `ColdRunner` when running the profile mode portion of the test. This resulted in the test being unable to clean up the project created by the test as DevTools was still holding onto a handle within the directory. This PR adds back the mistakenly removed DevTools shutdown logic in the `ColdRunner`.