Narrow Bisect : 
https://chromium.googlesource.com/chromium/src/+log/6487a75725fcfa61b963ca8d9abc8e8847fc002a..fc1a80d5d329dd4a1cce9886cadf85100f1edcb4?pretty=fuller&n=10000

Suspecting: r 408456 or 408453 ? from narrow bisect

@cbiesinger : Please help to re-assign if your change is not the cause for this issue.

Note : Issue is also seen on Linux (14.04 LTS) OS.

Deleted: Expected_text.mov 8.0 MB

Expected_text.mov 8.0 MB Download

Adding release block label, please undo if not the case.

Yes, this was caused by https://chromium.googlesource.com/chromium/src/+/955a53c8bc7f04b4830acabf7291c603314e0a53

The text is in a wrapping column flexbox, which we now overflow because we compute a cross size of max-content (?) or somesuch.

I'll have to check the flexbox spec to see what we should be doing.

This is marked as Beta blocker, Friendly ping to get the latest update on this from cbiesinger@

Tab -- the Flexbox spec confuses me, can you help explain? :-)

https://drafts.csswg.org/css-flexbox/#hypothetical-cross-size
"Determine the hypothetical cross size of each item by performing layout with the used main size and the available space, treating auto as fit-content."
(I assume auto should be content here)

What does this mean for a column flexbox? That is, what width should we lay it out into? We currently use max-content and I'm thinking maybe we should use fit-content in this specific case (when it's a flex-wrap box)

Just to update, issue is reproducible on latest canary version 54.0.2836.0.

Adding some more people who can maybe shed light on comment 5

Can we get an update on this issue marked as Beta blocker. Probable date for Beta launch is 2/3 weeks time from now. 

I'm going to revert the original patch (https://codereview.chromium.org/2289793003/) and will request merge approval once that lands. Need more time to fully investigate the issues.

@cbiesin

Do you have a reduction of the issue?

Sorry for the additional delay - I was moving into my new house last week. ^_^

I'm not sure what's unclear. :/  The main-axis size is fixed, and per the quote, you lay out into the available space for the cross axis.  Available space in both axises is defined in <https://drafts.csswg.org/css-flexbox/#algo-available>.

yfulgaonkar@ Are you still seeing this issue in latest Dev - 54.0.2840.6 and canary?

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/112c0577ad48a4cfe0b6046364f67bd97dc14eff

commit 112c0577ad48a4cfe0b6046364f67bd97dc14eff
Author: cbiesinger <cbiesinger@chromium.org>
Date: Thu Sep 01 01:54:43 2016

Revert of [css-flexbox] align-content should apply even when there's just a single line (patchset #2 id:20001 of https://codereview.chromium.org/2191683003/ )

Reason for revert:
Caused multiple regressions ( bug 634672 ,  bug 641789 ) and I'd like more time to investigate them before shipping this to users.

Original issue's description:
> [css-flexbox] align-content should apply even when there's just a single line
>
> In Jan 2015 the spec changed in
> https://drafts.csswg.org/css-flexbox/#change-201409-align-content-wrapping
>
> Change our code accordingly. This effectively reverts commit
> 764735dc12285a09a32b7d5ad3a8d6f178b0ab83
>
> BUG=599828
> R=eae@chromium.org,dgrogan@chromium.org
>
> Committed: https://crrev.com/955a53c8bc7f04b4830acabf7291c603314e0a53
> Cr-Commit-Position: refs/heads/master@{#408456}

TBR=dgrogan@chromium.org,eae@chromium.org
# Not skipping CQ checks because original CL landed more than 1 days ago.
BUG=599828, 634672 , 641789 

Review-Url: https://codereview.chromium.org/2289793003
Cr-Commit-Position: refs/heads/master@{#415844}

[modify] https://crrev.com/112c0577ad48a4cfe0b6046364f67bd97dc14eff/third_party/WebKit/LayoutTests/TestExpectations
[modify] https://crrev.com/112c0577ad48a4cfe0b6046364f67bd97dc14eff/third_party/WebKit/LayoutTests/css3/flexbox/alignContent-applies-with-flexWrap-wrap-with-single-line.html
[modify] https://crrev.com/112c0577ad48a4cfe0b6046364f67bd97dc14eff/third_party/WebKit/LayoutTests/css3/flexbox/flexbox-wordwrap.html
[modify] https://crrev.com/112c0577ad48a4cfe0b6046364f67bd97dc14eff/third_party/WebKit/LayoutTests/css3/flexbox/multiline-align-content.html
[modify] https://crrev.com/112c0577ad48a4cfe0b6046364f67bd97dc14eff/third_party/WebKit/Source/core/layout/LayoutFlexibleBox.cpp

Your change meets the bar and is auto-approved for M54 (branch: 2840)

Please merge your change to M54 (branch: 2840) before 5:00 PM PST Monday [09/05] if you would like to make it to M54 Beta promotion on Thursday [09/08].

I merged this in https://codereview.chromium.org/2309493002/, no idea why it's not showing up here. This is the branch commit: https://chromium.googlesource.com/chromium/src/+/829b6a7b22da492c51544d1f0e97ac23b5919467

Verified the Merge of reverted CL from C#14 and this is WAI as intended on the latest M-54(54.0.2840.14), Windows-10 , Mac OS 10.11.6 and Linux Ubuntu 14.04.

Adding the verified label therefore.

Deleted: 634672.png 612 KB

	634672.png 612 KB View Download

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/829b6a7b22da492c51544d1f0e97ac23b5919467

commit 829b6a7b22da492c51544d1f0e97ac23b5919467
Author: Christian Biesinger <cbiesinger@chromium.org>
Date: Fri Sep 02 18:55:18 2016

Revert of [css-flexbox] align-content should apply even when there's just a single line (patchset #2 id:20001 of https://codereview.chromium.org/2191683003/ )

Reason for revert:
Caused multiple regressions ( bug 634672 ,  bug 641789 ) and I'd like more time to investigate them before shipping this to users.

Original issue's description:
> [css-flexbox] align-content should apply even when there's just a single line
>
> In Jan 2015 the spec changed in
> https://drafts.csswg.org/css-flexbox/#change-201409-align-content-wrapping
>
> Change our code accordingly. This effectively reverts commit
> 764735dc12285a09a32b7d5ad3a8d6f178b0ab83
>
> BUG=599828
> R=eae@chromium.org,dgrogan@chromium.org
>
> Committed: https://crrev.com/955a53c8bc7f04b4830acabf7291c603314e0a53
> Cr-Commit-Position: refs/heads/master@{#408456}

TBR=dgrogan@chromium.org,eae@chromium.org
BUG=599828, 634672 , 641789 

Review-Url: https://codereview.chromium.org/2289793003
Cr-Commit-Position: refs/heads/master@{#415844}
(cherry picked from commit 112c0577ad48a4cfe0b6046364f67bd97dc14eff)

Review URL: https://codereview.chromium.org/2309493002 .

Cr-Commit-Position: refs/branch-heads/2840@{#130}
Cr-Branched-From: 1ae106dbab4bddd85132d5b75c670794311f4c57-refs/heads/master@{#414607}

[modify] https://crrev.com/829b6a7b22da492c51544d1f0e97ac23b5919467/third_party/WebKit/LayoutTests/TestExpectations
[modify] https://crrev.com/829b6a7b22da492c51544d1f0e97ac23b5919467/third_party/WebKit/LayoutTests/css3/flexbox/alignContent-applies-with-flexWrap-wrap-with-single-line.html
[modify] https://crrev.com/829b6a7b22da492c51544d1f0e97ac23b5919467/third_party/WebKit/LayoutTests/css3/flexbox/flexbox-wordwrap.html
[modify] https://crrev.com/829b6a7b22da492c51544d1f0e97ac23b5919467/third_party/WebKit/LayoutTests/css3/flexbox/multiline-align-content.html
[modify] https://crrev.com/829b6a7b22da492c51544d1f0e97ac23b5919467/third_party/WebKit/Source/core/layout/LayoutFlexibleBox.cpp

Minimized testcase.

You should see the full text "Buy", "Full Details", "Price Breaker" in the grey area

Deleted: SAE 90 Gear Oil For Manual Gearboxes.html 478 bytes

SAE 90 Gear Oil For Manual Gearboxes.html 478 bytes View Download

I'm adding a testcase for this bug in https://chromium-review.googlesource.com/c/chromium/src/+/1327746 (as flex-wrap-003.html)

flex-wrap-002.html in that patch shows this bug happening even without the patch that caused this regression.