frame_superres: Post encode/decode upscaling

This patch implements the post-encode and post-decode upscaling for the
frame superresolution experiment to work.

Upscaling happens after cdef and before loop restoration.

For now, this patch forces on random-superres.

The patch also cleans up some broken rate control hooks from VP9
days, to be brought back later when the resize and superres tools
are stable.

Change-Id: If0a8f69224dfaa0f4ae7703bd429ea2af953c7a6
diff --git a/av1/common/onyxc_int.h b/av1/common/onyxc_int.h
index ea265ec..be8a631 100644
--- a/av1/common/onyxc_int.h
+++ b/av1/common/onyxc_int.h
@@ -302,6 +302,8 @@
 #if CONFIG_FRAME_SUPERRES
   // The numerator of the superres scale; the denominator is fixed.
   uint8_t superres_scale_numerator;
+  int superres_upscaled_width;
+  int superres_upscaled_height;
 #endif  // CONFIG_FRAME_SUPERRES
 #if CONFIG_LOOP_RESTORATION
   RestorationInfo rst_info[MAX_MB_PLANE];