Make link to draft comment work

This is a bit of an edge case. We don't even show the "copy link"
button in the comment widget for drafts. But in the "publish panel"
we do show linkified line numbers, and they are currently producing
404s.

We had a user reporting an issue about this and it is super simple to
fix. So let's do that.

Release-Notes: skip
Google-Bug-Id: b/268271053
Change-Id: If97769019fbdd5fbdf933aa11b3e14487832ec26
diff --git a/polygerrit-ui/app/elements/core/gr-router/gr-router.ts b/polygerrit-ui/app/elements/core/gr-router/gr-router.ts
index 4f7d56f..997d9d5 100644
--- a/polygerrit-ui/app/elements/core/gr-router/gr-router.ts
+++ b/polygerrit-ui/app/elements/core/gr-router/gr-router.ts
@@ -1310,15 +1310,17 @@
     const repo = ctx.params[0] as RepoName;
     const commentId = ctx.params[2] as UrlEncodedCommentId;
 
-    const [comments, robotComments, change] = await Promise.all([
+    const [comments, robotComments, drafts, change] = await Promise.all([
       this.restApiService.getDiffComments(changeNum),
       this.restApiService.getDiffRobotComments(changeNum),
+      this.restApiService.getDiffDrafts(changeNum),
       this.restApiService.getChangeDetail(changeNum),
     ]);
 
     const comment =
       findComment(addPath(comments), commentId) ??
-      findComment(addPath(robotComments), commentId);
+      findComment(addPath(robotComments), commentId) ??
+      findComment(addPath(drafts), commentId);
     const path = comment?.path;
     const patchsets = computeAllPatchSets(change);
     const latestPatchNum = computeLatestPatchNum(patchsets);