On MacOS, following repo https://tinyurl.com/y6dzp9xz package manager fails to update the project due to permissions. This results in a crash when trying to save or retry opening the project.

Steps to reproduce.

1) Create a new project
2) Edit the manifest.json to point to the staging registry ("registry": "https://staging-packages.unity.com") and add "com.unity.xr.arcore": "2.1.0-preview.4" as a dependency.
3) Give the focus to Unity and wait until it finishes importing the package.
Notice issue >> Packages are not resolved, importing does not start. Try to save, exit and reopen. Crash.

Regressed from previous release 2019.2.0f1

Tested Broken: 2019.2.1f1
Tested Working: 2019.3.0a11, 2019.2.0b10, 2019.2.0f1.