I tested this with Dev and Canary, it is broken in Canary, but working in Dev, so we likely broke this in the last few days.  Not only does the "..." menu fail, but it also fails to share from the share icon in the top toolbar when an item is selected.

Jian, this may be related to a recent fix, can you take a look?

The bug is caused by the patch https://chromium-review.googlesource.com/c/chromium/src/+/1000552 which is landed after M67.

For now we don't have plan to merge the above patch to M67 since most of times the user should have already requested file permission storage when doing something on Downloads home.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/9eef8dcbfa7450d1d5792e5611321208249494b9

commit 9eef8dcbfa7450d1d5792e5611321208249494b9
Author: Jian Li <jianli@chromium.org>
Date: Sat Apr 28 00:27:05 2018

Check if storage permission is granted before requesting it

In DownloadController.requestFileAccess, we should check if storage
permission is already granted before requesting it.

Bug:  836397 
Change-Id: Idadcdfc3b055696b8f7194e5d63bdee54a8d4959
Reviewed-on: https://chromium-review.googlesource.com/1029116
Reviewed-by: Ted Choc <tedchoc@chromium.org>
Commit-Queue: Jian Li <jianli@chromium.org>
Cr-Commit-Position: refs/heads/master@{#554579}
[modify] https://crrev.com/9eef8dcbfa7450d1d5792e5611321208249494b9/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadController.java