Removing legacy compatibility layer.

Change-Id: I6fdcea0e0faf42386dd2b8f972a3b3fb2c21b2c7
diff --git a/y4minput.c b/y4minput.c
index bcc742a..34ea96d 100644
--- a/y4minput.c
+++ b/y4minput.c
@@ -1041,12 +1041,12 @@
   c_w *= bytes_per_sample;
   c_h = (_y4m->pic_h + _y4m->dst_c_dec_v - 1) / _y4m->dst_c_dec_v;
   c_sz = c_w * c_h;
-  _img->stride[PLANE_Y] = _img->stride[PLANE_ALPHA] =
+  _img->stride[VPX_PLANE_Y] = _img->stride[VPX_PLANE_ALPHA] =
       _y4m->pic_w * bytes_per_sample;
-  _img->stride[PLANE_U] = _img->stride[PLANE_V] = c_w;
-  _img->planes[PLANE_Y] = _y4m->dst_buf;
-  _img->planes[PLANE_U] = _y4m->dst_buf + pic_sz;
-  _img->planes[PLANE_V] = _y4m->dst_buf + pic_sz + c_sz;
-  _img->planes[PLANE_ALPHA] = _y4m->dst_buf + pic_sz + 2 * c_sz;
+  _img->stride[VPX_PLANE_U] = _img->stride[VPX_PLANE_V] = c_w;
+  _img->planes[VPX_PLANE_Y] = _y4m->dst_buf;
+  _img->planes[VPX_PLANE_U] = _y4m->dst_buf + pic_sz;
+  _img->planes[VPX_PLANE_V] = _y4m->dst_buf + pic_sz + c_sz;
+  _img->planes[VPX_PLANE_ALPHA] = _y4m->dst_buf + pic_sz + 2 * c_sz;
   return 1;
 }