*Description*
When a BehaviorGraphAgent with no assigned graph is selected in the Inspector, loading a graph from code fails for that GameObject upon entering Play mode.

*Steps to Reproduce*
# Create a new GameObject in the scene
# Add a script and an empty BehaviorGraphAgent (no graph assigned) to the GameObject
# Duplicate the GameObject
# Select one of the GameObjects (so the Inspector displays the BehaviorGraphAgent with no graph assigned)
# Enter Play mode

\\
*Actual results:* 
The selected GameObject's BehaviorGraphAgent's graph remains null, while the unselected one loads correctly.

*Expected results:* 
When entering Play mode, both GameObjects should have their BehaviorGraphAgent's graph properly assigned.

\\
*Reproducible with versions:* 
1.0.10, 1.0.11