Chrome Version: (copy from chrome://version)
OS: (e.g. Win10, MacOS 10.12, etc...)

What steps will reproduce the problem?
(1)run chromium with dchecks on
(2)open devtools
(3)attach devtools window on the bottom if it is not already there
(4)adjust height of devtools window

What is the expected result?
height adjusts accordingly

What happens instead?
devtools closes and dcheck failure log happens

The DCHECK is in the file layout_flexible_box.cc at line 319



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If this is a regression (i.e., worked before), please consider using the
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us identify the root cause and more rapidly triage the issue.

For graphics-related bugs, please copy/paste the contents of the about:gpu
page at the end of this report.