libvpx: Pull from upstream

source/libvpx/vp9/encoder/vp9_lookahead.c

Index: source/libvpx/vp9/encoder/vp9_lookahead.c
===================================================================
--- source/libvpx/vp9/encoder/vp9_lookahead.c	(revision 281795)
+++ source/libvpx/vp9/encoder/vp9_lookahead.c	(working copy)
@@ -18,18 +18,6 @@
 #include "vp9/encoder/vp9_extend.h"
 #include "vp9/encoder/vp9_lookahead.h"
 
-// The max of past frames we want to keep in the queue.
-#define MAX_PRE_FRAMES 1
-
-struct lookahead_ctx {
-  unsigned int max_sz;         /* Absolute size of the queue */
-  unsigned int sz;             /* Number of buffers currently in the queue */
-  unsigned int read_idx;       /* Read index */
-  unsigned int write_idx;      /* Write index */
-  struct lookahead_entry *buf; /* Buffer list */
-};
-
-
 /* Return the buffer at the given absolute index and increment the index */
 static struct lookahead_entry *pop(struct lookahead_ctx *ctx,
                                    unsigned int *idx) {