Fallback to default display if initial one is detached

Test: atest WindowContextTests
Fixes: 285630617
Change-Id: I196bab294c182230edda54241f7b725f44f05570
(cherry picked from commit 7d860098f5c585c96ce29b199b36f7c82b938249)
Merged-In: I196bab294c182230edda54241f7b725f44f05570
1 file changed