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In LayoutNG, when `box-decoration-break: clone` is set,
|NGInlineBoxState| clones the inline box fragments for every
line, but it had no effects in line breaking and measuring.

This patch implements the logic in |NGLineBreaker| so that
the property is taken account for line breaking, line width
(and therefore `text-align`), min-max sizing, etc.

|NGInlineNode::ComputeMinMaxSizes| started to hit DCHECK with
the |NGLineBreaker| change, because it computes `max-content`
from `min-content`. When this property clones box decorations
to every line, the logic does not work. This patch disables
the fast codepath, instead run a separate layout path when
this property is effective. This fixed an old crbug.com/612641.

This property is used ~0.7%. The regression crbug.com/1006599
got 10 stars.

Bug: 1006599, 612641
Change-Id: I6425fb5e7f8dc951d882eb90d1c081abd127468e
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2454349Reviewed-by: Yoshifumi Inoue <yosin@chromium.org>
Reviewed-by: Ian Kilpatrick <ikilpatrick@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/master@{#815477}