Collaborate starts loosing changes in the scene after updating. Pressing revert, it reverts to the last update, which also looses all the changes made in the scene, even though scene is saved.

To reproduce:
1. Create a new collaborate project
2. On the first machine make some changes and save the scene
3. On the second machine also make some changes and save the scene
4. On the first machine push the changes to the cloud
5. On the second machine update the project
6. Repeat steps 2 - 5 and after couple of times the bug starts to reproduce all the time

Expected result: scene is updated but the changes done locally are kept
Actual result: changes made to the scene are lost

Reproduced on: 5.5.5f1 5.6.3f1 2017.1.1f1 2017.3.0b3 spin#2