Switch to buffer sync when overriding sync-method to BLAST

When overriding a window's sync-method to BLAST, we need
to also make sure to increment the buffer-seq-id so that
we properly request the client to use BLAST sync.

Bug: 385976595
Test: atest WindowStateTests
Flag: com.android.window.flags.always_seq_id_layout
Change-Id: Ia114e9fc513c2e1342272d0605bc051205a7d963