We removed this adaption, which intended to reduce the size of
overlapped region if the neighboring block is a non-skip one. Thus,
now the width/height of the overlapping region is fixed as a half of
the current block.

Performance improvement (lowres/midres): 0.111%/0.102%

Change-Id: Ife75dad9d4eb355c78a05178b50cc015c442884f