Dragging to the content browser from an open import selection window will cause an assertion crash

Using a very specific way of importing an FBX will cause a crash assertion that closes the editor without opening crash reporter. Essentially when using the import button in the content browser and then navigating to the asset to import if you drag it from this open window into the CB it will cause the assertion after clicking import all.

Attached Video of import process

#. Open the Editor
#. Click Import in the Content Browser
#. Navigate to the FBX location and select it, but DO NOT click "open" from this window.
#. Drag the FBX from the open import window to the content browser.
#. Click Import All on the import options window
#. Should get Error message at this point.
#. Click cancel in the Import Window first opened and you should get the hard crash.

Regression: No

Results: Editor will crash

Expected: Should not crash

No crash reporter window opened to generate call stack.

Taken from the log:

[2016.06.21-14.02.06:210][740]LogWindows: Windows GetLastError: The operation completed successfully. (0)
[2016.06.21-14.02.06:210][740]LogCrashTracker:

[740]LogWindows:Error: === Critical error: ===
Fatal error: [Link Removed] [Line: 669]
Shader Compiling thread exception:
Assertion failed: ShaderFormats.Num() [Link Removed] [Line: 172]

[740]LogExit: Executing StaticShutdownAfterError
[740]LogWindows: FPlatformMisc::RequestExit(1)