1933566 - Take 'block-size:stretch' into consideration when considering inline-axis intrinsic size contributions

Status: NEW

(Core :: Layout, task)

Description

[Daniel Holbert [:dholbert]]

Attachment: testcase 1

STR:

1. Enable either or both of these about:config prefs:

layout.css.stretch-size-keyword.enabled
layout.css.webkit-fill-available.enabled

2. Load attached testcase, comparing the top half to the bottom half.

EXPECTED RESULTS:
The two halves should look the same.

ACTUAL RESULTS:
Black-bordered area (and its blue-bordered sub-area) are skinnier in the upper half. (With my current patch stack from bug 1933408 which makes the testcase actually do something nontrivial, we size the upper teal canvas to be as wide as it is in the bottom half, but its containers are still too skinny.)

Notes:

• The top half uses stretch (with the -webkit-fill-available alias as a fallback), while the bottom half uses an equivalent calc() expression.
• Chrome gives EXPECTED RESULTS, whereas WebKit sort-of matches Firefox; so that variability suggests there isn't a huge webcompat dependence on this behavior. Still, Chrome's behavior seems preferable.

(The frame-state flags in bug 1933554 might be relevant here; not sure. Putting that in see-also in case one bug fixes the other in part or in whole.)