Steps to reproduce:
1. Open user attached project
2. Untick "default is native resolution" in player settings
3. Build and run the project
4. Go to fullscreen (alt+enter)
5. Notice that the resolution is not the current resolution of the desktop

Expected result: when in fullscreen mode, Screen.currentResolution should return the current resolution of the desktop

Reproduced in: 2018.1.0b1, 2017.3.0p1, 2017.2.1p1, 2017.1.3f1, 5.6.5f1, 5.5.6f1, 5.4.6f3

Tested on Windows 10 and Mac 10.12.3