This is reproducible only for offline page downloads.

I discovered the issue. On startup before querying Offline Pages model, we check whether it has been loaded and, if not, not query it. 
However, after  issue 668174  (https://codereview.chromium.org/2536573003) Offline Pages model just collects all requests before it has been loaded and processes them after finishing loading.

This code (on both sides) is present in M57.0.2987.38. However, I could not reproduce the bug, I tried:
- Nexus 6P and one offline page - 0/5;
- Nexus 6P and >10 offline pages - 0/5;
- Low end Moto and one offline page - 0/5;
- Low end Moto and >10 offline pages - 0/5;

I suspect that Offline Pages may have introduced something in M58, which triggered this bug. I feel like a merge into M57 is not needed.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/600636adf773150653cf033c94649a75f7d3b2fb

commit 600636adf773150653cf033c94649a75f7d3b2fb
Author: vitaliii <vitaliii@chromium.org>
Date: Fri Feb 10 13:22:32 2017

[NTP:Downloads] Request offline pages even if model is not loaded.

Do not check whether Offline Pages model has been loaded when requesting
offline pages. Currently the model simply collects all requests and
answers them when it is loaded. In this CL Downloads provider waits for
the model to answer instead of not showing offline pages on startup.

BUG= 690391 

Review-Url: https://codereview.chromium.org/2683383002
Cr-Commit-Position: refs/heads/master@{#449603}

[modify] https://crrev.com/600636adf773150653cf033c94649a75f7d3b2fb/chrome/browser/ntp_snippets/download_suggestions_provider.cc
[modify] https://crrev.com/600636adf773150653cf033c94649a75f7d3b2fb/chrome/browser/ntp_snippets/download_suggestions_provider_unittest.cc

Hi treib@,

Do you think we should merge this? The issue itself is pretty minor, but the fix is simple as well, so I am tempted to merge, especially keeping in mind that downloads are important for EM.

Verified in 58.0.3012.0 build

I actually prefer to merge it, even though I could not reproduce it on my testing devices. There may be slower devices on which this is more likely to occur.

Verified (5/5) in M58.0.3014.0.

I am requesting to merge the CL from comment #3 to M57.

Sorry, I missed the question in #4.
If you're reasonably confident this fix doesn't break anything else, then I think it's fine to merge. Ultimately it's your call as a committer :)

Your change meets the bar and is auto-approved for M57. Please go ahead and merge the CL to branch 2987 manually. Please contact milestone owner if you have questions.
Owners: amineer@(clank), cmasso@(bling), ketakid@(cros), govind@(desktop)

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

treib@, no problem. The fix looks very simple and I am going to test it before landing.

Unfortunately, currently 2987 cannot be compiled (presumably due to a merge of  issue 690266 ). I notified the owner of that merge and I will have to wait until they address it before I can tests my merge.

Actually, I need to merge https://codereview.chromium.org/2667073003 first ( issue 669404 ). Both are simple and small CLs, so I am still going to proceed with the merge.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/58ecbe8cb269156ac6fd6c30c837bd8d918e9b2a

commit 58ecbe8cb269156ac6fd6c30c837bd8d918e9b2a
Author: Vitalii Iarko <vitaliii@chromium.org>
Date: Mon Feb 20 15:28:06 2017

Merge "[NTP:Downloads] Request offline pages even if model is not ..."

This is a merge of https://codereview.chromium.org/2683383002 into M57
(branch 2987).

Previously another CL (https://codereview.chromium.org/2667073003) was
merged as well (see https://codereview.chromium.org/2706863002), in
order to avoid conflicts when merging this one.

There were no conflicts, both CLs has been tested on two devices and
unittests.

Original description:

Do not check whether Offline Pages model has been loaded when requesting
offline pages. Currently the model simply collects all requests and
answers them when it is loaded. In this CL Downloads provider waits for
the model to answer instead of not showing offline pages on startup.

BUG= 690391 

Review-Url: https://codereview.chromium.org/2683383002
Cr-Commit-Position: refs/heads/master@{#449603}
(cherry picked from commit 600636adf773150653cf033c94649a75f7d3b2fb)

Review-Url: https://codereview.chromium.org/2704203002 .
Cr-Commit-Position: refs/branch-heads/2987@{#598}
Cr-Branched-From: ad51088c0e8776e8dcd963dbe752c4035ba6dab6-refs/heads/master@{#444943}

[modify] https://crrev.com/58ecbe8cb269156ac6fd6c30c837bd8d918e9b2a/chrome/browser/ntp_snippets/download_suggestions_provider.cc
[modify] https://crrev.com/58ecbe8cb269156ac6fd6c30c837bd8d918e9b2a/chrome/browser/ntp_snippets/download_suggestions_provider_unittest.cc