Untangle HarfBuzz callbacks for glyph width and extents

Untangle HarfBuzz callbacks for glyph width and extents

Under the hood, SkPaint uses "needsFullMetrics" or just advance
callbacks into the glyph cache. Untangling the calls and only retrieving
either advance or bounds should speed up these HarfBuzz callbacks.

Measured locally I am seeing ~10% improvements on
blink_pref.layout:chapter-reflow and
~blink_pref.layout:ArabicLineLayout.

BUG=631032
R=kojii,tzik

Committed: https://crrev.com/994c65ef57ec7c84b18fd66d7b8b85e5a2dc29bd
Cr-Commit-Position: refs/heads/master@{#409295}

[drott, 2016-08-02 12:59:30]

The CQ bit was checked by drott@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-08-02 12:59:44]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[drott, 2016-08-02 13:00:26]

The CQ bit was checked by drott@chromium.org to run a CQ dry run

[drott, 2016-08-02 13:00:33]

drott@chromium.org changed reviewers:
+ eae@chromium.org

[commit-bot: I haz the power, 2016-08-02 13:00:34]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[eae, 2016-08-02 16:16:20]

LGTM

Very nice!

[kojii, 2016-08-02 16:20:24]

lgtm, very nice from me too!

[commit-bot: I haz the power, 2016-08-02 17:03:52]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-02 17:03:53]

Dry run: This issue passed the CQ dry run.

[drott, 2016-08-02 20:05:01]

The CQ bit was checked by drott@chromium.org

[commit-bot: I haz the power, 2016-08-02 20:05:57]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-02 20:11:31]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2016-08-02 20:13:34]

Description was changed from

==========
Untangle HarfBuzz callbacks for glyph width and extents

Under the hood, SkPaint uses "needsFullMetrics" or just advance
callbacks into the glyph cache. Untangling the calls and only retrieving
either advance or bounds should speed up these HarfBuzz callbacks.

Measured locally I am seeing ~10% improvements on
blink_pref.layout:chapter-reflow and
~blink_pref.layout:ArabicLineLayout.

BUG=631032
R=kojii,tzik
==========

to

==========
Untangle HarfBuzz callbacks for glyph width and extents

Under the hood, SkPaint uses "needsFullMetrics" or just advance
callbacks into the glyph cache. Untangling the calls and only retrieving
either advance or bounds should speed up these HarfBuzz callbacks.

Measured locally I am seeing ~10% improvements on
blink_pref.layout:chapter-reflow and
~blink_pref.layout:ArabicLineLayout.

BUG=631032
R=kojii,tzik

Committed: https://crrev.com/994c65ef57ec7c84b18fd66d7b8b85e5a2dc29bd
Cr-Commit-Position: refs/heads/master@{#409295}
==========

[commit-bot: I haz the power, 2016-08-02 20:13:35]

Patchset 2 (id:??) landed as
https://crrev.com/994c65ef57ec7c84b18fd66d7b8b85e5a2dc29bd
Cr-Commit-Position: refs/heads/master@{#409295}