Steps to reproduce:
1. Set up a perforce server and enable integration on Unity on any project
2. Create a handful of files (new scripts for example)
3. Download "clumsy.zip" app attached
4. Open and check Lag, set it to about 200-500 ms (The more you set it the more visible it is) and start
5. Now, most of the time, when you click on a file in your project an fstat command will be issued which will freeze the editor until it completes
6. You can also move focus from the editor to another window and back to make the fstats appear again, if they stop

Expected result: The editor does not freeze except when saving, or doing explicit version control operations
Actual result: Editor freezes on fstat command and becomes unusable when it happens a lot in sequence

Reproduced on:5.6.0f1, 5.6.2p1, 2017.1.0f2
Regression introduced in: 5.6.0b10
Not reproduced on: 5.5.4p1, 5.6.0b1, 5.6.0b8, 5.6.0b9

Note: Bug only appears if your inspector is active. Possibly caused by "IsOpenForEdit" call of the Inspector.