commit 8bbe4f276630745041c421453568353db65b9e7e
author Peng Zhou <zhoupeng.1996@bytedance.com> Fri Nov 18 06:02:28 2022
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> Fri Nov 18 06:02:28 2022
tree a1aa62dfa04b73bed64f089b15a7644933fda41c
parent 305a1f6083f6b253e7a5b244b52d5aeb0f34ad3a

NGLineBreaker::ShapeText re-shape the specified range defined by `start` to `end` of `NGInlineItem`

Before this patch, if some custom fonts that render a line of
extremely long texts, it will lead to jank.

NGLineBreaker::ShapeText re-shape the specified range of `NGInlineItem`,
but when `items_data_.segments` is nullptr will
re-shape the whole segment, not defined by `start` to `end`.
If rendered extremely long texts will be split into n lines,
the whole segment will be re-shaped n times.
When `font-family` has m custom fonts,
FontFallbackIterator::Next will try to traverse
the segment to find FontDataForRangeSet.
So the whole segment will be traversed m * n times.

With this patch, NGLineBreaker::ShapeText re-shape
the specified range defined by `start` to `end`
whether items_data_.segments is nullptr or not.

Bug: 1385798

Change-Id: I7baff10a5fd5a2156c6a3f5eec86dc025d939da7
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/4033811
Reviewed-by: Koji Ishii <kojii@chromium.org>
Commit-Queue: Koji Ishii <kojii@chromium.org>
Cr-Commit-Position: refs/heads/main@{#1073227}