Eliminate bo->content_length

bin/varnishd/cache/cache.h

@@ -517,8 +517,6 @@ struct busyobj {
 
 	struct pool_task	fetch_task;
 
-	ssize_t			content_length;
-
 	enum sess_close		doclose;
 
 #define BO_FLAG(l, r, w, d) unsigned	l:1;

bin/varnishd/cache/cache_busyobj.c

@@ -149,7 +149,6 @@ VBO_GetBusyObj(struct worker *wrk, const struct req *req)
 	VCL_Ref(bo->vcl);
 
 	bo->t_first = bo->t_prev = NAN;
-	bo->content_length = -1;
 	bo->doclose = SC_NULL;
 
 	return (bo);

bin/varnishd/cache/cache_fetch.c

@@ -349,7 +349,6 @@ vbf_stp_startfetch(struct worker *wrk, struct busyobj *bo)
 		wrk->stats.fetch_chunked++;
 	} else if (bo->htc->body_status == BS_LENGTH) {
 		assert(bo->htc->content_length > 0);
-		bo->content_length = bo->htc->content_length;
 		wrk->stats.fetch_length++;
 	} else if (bo->htc->body_status == BS_EOF) {
 		wrk->stats.fetch_eof++;
@@ -451,7 +450,7 @@ vbf_fetch_body_helper(struct busyobj *bo)
 
 	AN(vfc->vfp_nxt);
 
-	est = bo->content_length;
+	est = bo->htc->content_length;
 	if (est < 0)
 		est = 0;