The same applies to the align-content and justify-content properties.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/841ce846af10f5855f09fa7db77dd53e680080bf

commit 841ce846af10f5855f09fa7db77dd53e680080bf
Author: Javier Fernandez <jfernandez@igalia.com>
Date: Tue Jan 23 00:17:35 2018

[css-align] The 'left' and 'right' values must be invalid in block axis

The CSS WG resolved to remove the 'left' and 'right' values from the
block/cross axis alignment properties.

https://github.com/w3c/csswg-drafts/issues/1403

This CL changes the CSS parsing logic of all the CSS Box Alignment
properties, both block-axis (align-{self, items, content} and
inline-axis (justify-{self, items, content}).

Additionally, the alignment shorthands (place-{self, items, content})
have been also changed to respect the new syntax.

This change also affects the Grid Layout alignment logic.

Bug:  802095 
Change-Id: Id848ce22a9b2d69ecf2bfd58503f590e4b2fe4db
Reviewed-on: https://chromium-review.googlesource.com/877519
Reviewed-by: meade_(do not use) <meade@chromium.org>
Commit-Queue: Javier Fernandez <jfernandez@igalia.com>
Cr-Commit-Position: refs/heads/master@{#531074}
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[modify] https://crrev.com/841ce846af10f5855f09fa7db77dd53e680080bf/third_party/WebKit/LayoutTests/external/wpt/css/css-align/resources/alignment-parsing-utils.js
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[modify] https://crrev.com/841ce846af10f5855f09fa7db77dd53e680080bf/third_party/WebKit/LayoutTests/external/wpt/css/css-align/self-alignment/parse-align-self-004.html
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Have we shipped support? If so, should we have a Deprecate and Remove?

Umm, I might have asked for Deprecate and Remove, indeed. However, these two values were removed from the spec back in june already and were doing nothing for the CSS properties affected by this change. I thought it was clearly zero interop risk, but I agree that I should have send the forma request to the mailing list.

I don't mind to roll it out and send the formal request if anybody considers it more convenient. 

This issue should be FIXED now.