libvpx: Pull from upstream

source/libvpx/vpx/src/vpx_decoder.c

Index: source/libvpx/vpx/src/vpx_decoder.c
===================================================================
--- source/libvpx/vpx/src/vpx_decoder.c	(revision 251189)
+++ source/libvpx/vpx/src/vpx_decoder.c	(working copy)
@@ -226,3 +226,21 @@
 
   return SAVE_STATUS(ctx, res);
 }
+
+vpx_codec_err_t vpx_codec_set_frame_buffer_functions(
+    vpx_codec_ctx_t *ctx, vpx_get_frame_buffer_cb_fn_t cb_get,
+    vpx_release_frame_buffer_cb_fn_t cb_release, void *cb_priv) {
+  vpx_codec_err_t res;
+
+  if (!ctx || !cb_get || !cb_release) {
+    res = VPX_CODEC_INVALID_PARAM;
+  } else if (!ctx->iface || !ctx->priv ||
+             !(ctx->iface->caps & VPX_CODEC_CAP_EXTERNAL_FRAME_BUFFER)) {
+    res = VPX_CODEC_ERROR;
+  } else {
+    res = ctx->iface->dec.set_fb_fn(ctx->priv->alg_priv, cb_get, cb_release,
+                                    cb_priv);
+  }
+
+  return SAVE_STATUS(ctx, res);
+}