libsuspend: wait for earlysuspend transition to finish

Wait for the early suspend transition to finish to the point where
surfaceflinger would previously have synchronized.  This is important
during screen on, to ensure the display early suspend handlers have
completed before surfaceflinger unblanks.

Change-Id: I91ac0253d9655c3f1ae3dd7f1a918c279568b23e
1 file changed