Viewport deselect hotkey no longer works

BRANCH: MAIN
CHANGELIST: 2374441
PLATFORM: Windows

DESCRIPTION: The functionality to use the hotkey to deselect an object in the viewport using the ESC key no longer works in 4.7 without first selecting any tab that is not the viewport.

ATTACHED:

ENVIRONMENT:
OS: Windows 8.1
PROCESSOR: Intel(R) Xeon(R) CPU E5-2620 @ 2.10GHz
MEMORY: 32GB RAM
GRAPHICS: NVIDIA GeForce GTX 770

FREQUENCY: 3/3
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REPRO STEPS:

1. Open UE4 4.7 Preview 1
2. Place an asset in the view port
3. Press ESC key

Expected: In previous versions the ESC key would deselect the asset that was selected in the viewport.

RESULTS: The asset selected in the viewport will no longer be deselected when pressing the ESC key, unless the the viewport is not the main focus. Ie. select the scene outliner or details panel and hit ESC to see functionality.