I've managed to repro this on kevin and caroline on 68, but not on 69. I have an iPhone 8 running 11.4.

+cc thestig, who's been making changes to MTP code. I've narrowed the fix to between 69.0.3452 and 69.0.3455.1

I'm currently bisecting CLs to find the fix.

Was fixed in:
https://chromium.googlesource.com/chromium/src/+/44663e8f02729bf01d296ce86087f87168420713

I'll see if it can be merged into 68, or if the original breakage needs to be reverted instead (in the release branch).

A clean merge to 68 is possible if both crrev.com/3d7f15c742e7aff293b9b2065837bf98cb3a042b and crrev.com/44663e8f02729bf01d296ce86087f87168420713 are cherry-picked.

@thestig, WDYT?

The cherry-picks in comment 6 sound ok, but what would be the revert option? Can you check where this broke?

Breakage was caused by crrev.com/aaa4d5aa673b0e9f9973bc38386f95f59e2fb3ec

I tried reverting it in the 68 branch, but after having to also revert 4 follow-ups, I couldn't get a build. I think the best option is to merge the two I mentioned in comment 6. There are too many changes to go backwards.

Requesting a merge of crrev.com/3d7f15c742e7aff293b9b2065837bf98cb3a042b and crrev.com/44663e8f02729bf01d296ce86087f87168420713

Servicification of MTP has broken it under M68. There are too many follow-up changes to do a graceful revert in the 68 branch, but the two requested patches merge cleanly and fix the issue.

This bug requires manual review: M68 has already been promoted to the beta branch, so this requires manual review
Please contact the milestone owner if you have questions.
Owners: cmasso@(Android), kariahda@(iOS), bhthompson@(ChromeOS), abdulsyed@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

SGTM.

Thanks for the details on alternatives and testing. Bernie is out, I will approve this for merge in M68.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/99180f2481b702ae4928a92b1dd39231996ede2d

commit 99180f2481b702ae4928a92b1dd39231996ede2d
Author: Lei Zhang <thestig@chromium.org>
Date: Tue Jul 10 00:24:16 2018

[M68] Align GetFileInfo() between MtpManager and MtpDaemonClient.

TBR=thestig@chromium.org
BUG= 858899 

Align GetFileInfo() between MtpManager and MtpDaemonClient.

MediaTransferProtocolDaemonClient currently provides a low-level
GetFileInfo() method, and MtpManager does the translation to the
high-level GetFileInfo() method that MTPDeviceTaskHelper understands.

Change MtpManager's GetFileInfo() from the high-level method to the
low-level method, so it acts more like a pass-through. Make
MTPDeviceTaskHelper handle the translation.

BUG= 769630 

Change-Id: I21e20b71d333a1ee7173071f04aaf2e37dd61844
Reviewed-on: https://chromium-review.googlesource.com/1080212
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#565413}(cherry picked from commit 3d7f15c742e7aff293b9b2065837bf98cb3a042b)
Reviewed-on: https://chromium-review.googlesource.com/1130715
Reviewed-by: Anand Mistry <amistry@chromium.org>
Cr-Commit-Position: refs/branch-heads/3440@{#624}
Cr-Branched-From: 010ddcfda246975d194964ccf20038ebbdec6084-refs/heads/master@{#561733}
[modify] https://crrev.com/99180f2481b702ae4928a92b1dd39231996ede2d/chrome/browser/media_galleries/chromeos/mtp_device_task_helper.cc
[modify] https://crrev.com/99180f2481b702ae4928a92b1dd39231996ede2d/chrome/browser/media_galleries/chromeos/mtp_device_task_helper.h
[modify] https://crrev.com/99180f2481b702ae4928a92b1dd39231996ede2d/components/storage_monitor/test_media_transfer_protocol_manager_chromeos.cc
[modify] https://crrev.com/99180f2481b702ae4928a92b1dd39231996ede2d/components/storage_monitor/test_media_transfer_protocol_manager_chromeos.h
[modify] https://crrev.com/99180f2481b702ae4928a92b1dd39231996ede2d/services/device/media_transfer_protocol/media_transfer_protocol_manager.cc
[modify] https://crrev.com/99180f2481b702ae4928a92b1dd39231996ede2d/services/device/media_transfer_protocol/media_transfer_protocol_manager.h
[modify] https://crrev.com/99180f2481b702ae4928a92b1dd39231996ede2d/services/device/media_transfer_protocol/mtp_device_manager.cc
[modify] https://crrev.com/99180f2481b702ae4928a92b1dd39231996ede2d/services/device/media_transfer_protocol/mtp_device_manager.h
[modify] https://crrev.com/99180f2481b702ae4928a92b1dd39231996ede2d/services/device/public/mojom/mtp_manager.mojom

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/1530ae01b4687f98b62ee816762ac1042ea2b270

commit 1530ae01b4687f98b62ee816762ac1042ea2b270
Author: Lei Zhang <thestig@chromium.org>
Date: Tue Jul 10 00:27:57 2018

[M68] Replace MtpManager's ReadDirectory() with ReadDirectoryEntryIds().

TBR=thestig@chromium.org
BUG= 858899 

Replace MtpManager's ReadDirectory() with ReadDirectoryEntryIds().

MediaTransferProtocolDaemonClient currently provides a low-level
ReadDirectoryEntryIds() method, and MtpManager does the translation to
the high-level ReadDirectory() method that MTPDeviceTaskHelper
understands.

Change MtpManager's ReadDirectory() method to ReadDirectoryEntryIds(),
so it acts more like a pass-through. Make MTPDeviceTaskHelper handle the
translation.

BUG= 769630 

Change-Id: I5154bd4beac0b6ab15579f166cdf8b8add6a7dac
Reviewed-on: https://chromium-review.googlesource.com/1080214
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Colin Blundell <blundell@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#565441}(cherry picked from commit 44663e8f02729bf01d296ce86087f87168420713)
Reviewed-on: https://chromium-review.googlesource.com/1130735
Reviewed-by: Anand Mistry <amistry@chromium.org>
Cr-Commit-Position: refs/branch-heads/3440@{#625}
Cr-Branched-From: 010ddcfda246975d194964ccf20038ebbdec6084-refs/heads/master@{#561733}
[modify] https://crrev.com/1530ae01b4687f98b62ee816762ac1042ea2b270/chrome/browser/media_galleries/chromeos/mtp_device_task_helper.cc
[modify] https://crrev.com/1530ae01b4687f98b62ee816762ac1042ea2b270/chrome/browser/media_galleries/chromeos/mtp_device_task_helper.h
[modify] https://crrev.com/1530ae01b4687f98b62ee816762ac1042ea2b270/components/storage_monitor/test_media_transfer_protocol_manager_chromeos.cc
[modify] https://crrev.com/1530ae01b4687f98b62ee816762ac1042ea2b270/components/storage_monitor/test_media_transfer_protocol_manager_chromeos.h
[modify] https://crrev.com/1530ae01b4687f98b62ee816762ac1042ea2b270/services/device/media_transfer_protocol/media_transfer_protocol_manager.cc
[modify] https://crrev.com/1530ae01b4687f98b62ee816762ac1042ea2b270/services/device/media_transfer_protocol/media_transfer_protocol_manager.h
[modify] https://crrev.com/1530ae01b4687f98b62ee816762ac1042ea2b270/services/device/media_transfer_protocol/mtp_device_manager.cc
[modify] https://crrev.com/1530ae01b4687f98b62ee816762ac1042ea2b270/services/device/media_transfer_protocol/mtp_device_manager.h
[modify] https://crrev.com/1530ae01b4687f98b62ee816762ac1042ea2b270/services/device/public/mojom/mtp_manager.mojom

I've flashed 68.0.3440.57 and checked that I can now access the photos on my iPhone.

Verified on ChromeOS 10718.50.0, 68.0.3440.59 beta-channel eve, minnie