Fix SetInputWindow_InputWindowInfo takes too long

Test case SetInputWindow_InputWindowInfo would wait inject event until
timeout that would take too long (> 400ms) to complete.
This patch would change the test to release one window input channel
and detect if another focused window can recevied the key event after
setInputWindow intead of waiting until timeout.

Bug: 123488846
Test: atest inputflinger_tests
Change-Id: I9cf0f199dc80bef70e0c2cd4af73b2221450a01d