Surface: Use buffer id to synchronize slots

For the same buffer, GraphicBuffer's buffer_handle_t* may change when
doing attach/detach. Use Id instead.

Test: Call attach/detach, and observe mRemovedBuffers is updated
Bug: 38238747
Change-Id: I6ab1ae5340565f98cb981b7e38c31a4f85190e56
1 file changed