Animations and source control, when editing playable assets in the animations window it would be nice if there was some kind of perforce integration to checkout and prompt user before checking out the asset. The current integration just auto checks out which is not in line with how any other asset editing works where the content is greyed out until a checkout button is clicked.

1. Open attached project "Animation.zip" inside perforce workspace
2. Enable Perforce, add Assets contents and submit everything so nothing would be checked out
3. Double-click Assets/TransformChange.anim to open it in animation window
4. Notice that keyframes/curves can be edited, new keyframes can be added even though animation file is not checked out.

Actual behaviour: Animation properties can be changed even though asset is not checked out. Check out happens whenever editor decides to save asset changes in memory to disk.

Expected behaviour: Animation properties cannot be changed until animation asset is checked out - this would be in-line with editing various assets in inspector that, like animations, don't need user to initiate save operation manually.

Reproduced: 2018.2.18f1, 2018.3.0b12, 2019.1.0a11