Revert "Do not render empty comments (go-gitea#29039)"

This reverts commit b4513f4.

Author: earl-warren

routers/web/repo/pull_review.go

@@ -153,19 +153,12 @@ func UpdateResolveConversation(ctx *context.Context) {
 }
 
 func renderConversation(ctx *context.Context, comment *issues_model.Comment, origin string) {
-	ctx.Data["PageIsPullFiles"] = origin == "diff"
-
 	comments, err := issues_model.FetchCodeCommentsByLine(ctx, comment.Issue, ctx.Doer, comment.TreePath, comment.Line, ctx.Data["ShowOutdatedComments"].(bool))
 	if err != nil {
 		ctx.ServerError("FetchCodeCommentsByLine", err)
 		return
 	}
-	if len(comments) == 0 {
-		// if the comments are empty (deleted, outdated, etc), it doesn't need to render anything, just return an empty body to replace "conversation-holder" on the page
-		ctx.Resp.WriteHeader(http.StatusOK)
-		return
-	}
-
+	ctx.Data["PageIsPullFiles"] = (origin == "diff")
 	ctx.Data["comments"] = comments
 	if ctx.Data["CanMarkConversation"], err = issues_model.CanMarkConversation(ctx, comment.Issue, ctx.Doer); err != nil {
 		ctx.ServerError("CanMarkConversation", err)
@@ -186,8 +179,6 @@ func renderConversation(ctx *context.Context, comment *issues_model.Comment, ori
 		ctx.HTML(http.StatusOK, tplDiffConversation)
 	} else if origin == "timeline" {
 		ctx.HTML(http.StatusOK, tplTimelineConversation)
-	} else {
-		ctx.Error(http.StatusBadRequest, "Unknown origin: "+origin)
 	}
 }