Add more logs for WindowContextController

Change the mAttachedToDisplayArea from boolean to
int which should help us to know the reason when
there is a issue happened due to this flag.

Add more logs to clarify the exception reason when
WindowContextController calling attachToWindowToken
but the WindowTokenClient haven't been associated
with a display area.

Bug: 211062619
Bug: 220049234
Test: atest WindowContextControllerTest

Change-Id: I5e3832a466d47de5aafb32cf5fbf9c375a65160a