Reland: Move glyph lookup to hb-ot-font and remove glyph cache in HarfBuzzFace

Reland: Move glyph lookup to hb-ot-font and remove glyph cache in HarfBuzzFace

Relanding after previously reverted because it caused linkage issues
for chromeos=1 developer builds in Linux. These should be addressed
now through dpranke@'s fixes in issue 589342.

Together with Behdad we identified several ways to optimize and cleanup
HarfBuzzFace:
* We moved the glyph lookup completely to the built-in HarfBuzz
  implementation in hb-ot-font.
* This allows us to remove the unbounded glyph cache we kept around in
  HarfBuzzFace.
* We also moved instantantion and ownership of HarfBuzzFontData to
  HarfBuzzFace. We only update the size and unicode-range on each call
  to getScaledFont(), saving us as the allocation and setup costs of
  this object for each shaping call.
* We removed the unneeded callback for retrieving the horizontal origin,
  which was implemented as a noop.

In local measurements on Mac this leads to large improvements in the
blink_perf.layout tests, especially in
chapter-reflow-once-random (>130%), flexbox-lots-of-data (>58%) and
ArabicLineLayout (>26%) with only a few of the microbenchmarks being
slightly slower: So this is an improvement for layout cases that do not
profit much from the word cache.

TBR'ing since this has previously been LGTMed in
https://codereview.chromium.org/1733193002

BUG=589340
TBR=eae,behdad,kojii

Committed: https://crrev.com/b2a8582e83ef3022ac1cc65648348dfd168b77cd
Cr-Commit-Position: refs/heads/master@{#385631}

[drott, 2016-04-06 22:30:31]

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

[commit-bot: I haz the power, 2016-04-06 22:30:58]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1866863002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1866863002/1

[drott, 2016-04-06 22:31:12]

Dirk's changes landed \o/, and I think this should be finally good to go, yay!

[commit-bot: I haz the power, 2016-04-07 00:46:18]

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

[commit-bot: I haz the power, 2016-04-07 00:46:19]

Dry run: This issue passed the CQ dry run.

[drott, 2016-04-07 02:33:27]

Description was changed from

==========
Reland: Move glyph lookup to hb-ot-font and remove glyph cache in HarfBuzzFace

Relanding after previously reverted because it caused linkage issues
for chromeos=1 developer builds in Linux. These should be addressed
now through dpranke@'s fixes in issue 589342.

Together with Behdad we identified several ways to optimize and cleanup
HarfBuzzFace:
* We moved the glyph lookup completely to the built-in HarfBuzz
  implementation in hb-ot-font.
* This allows us to remove the unbounded glyph cache we kept around in
  HarfBuzzFace.
* We also moved instantantion and ownership of HarfBuzzFontData to
  HarfBuzzFace. We only update the size and unicode-range on each call
  to getScaledFont(), saving us as the allocation and setup costs of
  this object for each shaping call.
* We removed the unneeded callback for retrieving the horizontal origin,
  which was implemented as a noop.

In local measurements on Mac this leads to large improvements in the
blink_perf.layout tests, especially in
chapter-reflow-once-random (>130%), flexbox-lots-of-data (>58%) and
ArabicLineLayout (>26%) with only a few of the microbenchmarks being
slightly slower: So this is an improvement for layout cases that do not
profit much from the word cache.

BUG=589340
R=eae,behdad,kojii
==========

to

==========
Reland: Move glyph lookup to hb-ot-font and remove glyph cache in HarfBuzzFace

Relanding after previously reverted because it caused linkage issues
for chromeos=1 developer builds in Linux. These should be addressed
now through dpranke@'s fixes in issue 589342.

Together with Behdad we identified several ways to optimize and cleanup
HarfBuzzFace:
* We moved the glyph lookup completely to the built-in HarfBuzz
  implementation in hb-ot-font.
* This allows us to remove the unbounded glyph cache we kept around in
  HarfBuzzFace.
* We also moved instantantion and ownership of HarfBuzzFontData to
  HarfBuzzFace. We only update the size and unicode-range on each call
  to getScaledFont(), saving us as the allocation and setup costs of
  this object for each shaping call.
* We removed the unneeded callback for retrieving the horizontal origin,
  which was implemented as a noop.

In local measurements on Mac this leads to large improvements in the
blink_perf.layout tests, especially in
chapter-reflow-once-random (>130%), flexbox-lots-of-data (>58%) and
ArabicLineLayout (>26%) with only a few of the microbenchmarks being
slightly slower: So this is an improvement for layout cases that do not
profit much from the word cache.

TBR'ing since this has previously been LGTMed in 
https://codereview.chromium.org/1733193002

BUG=589340
TBR=eae,behdad,kojii
==========

[drott, 2016-04-07 02:33:30]

The CQ bit was checked by drott@chromium.org

[commit-bot: I haz the power, 2016-04-07 02:34:02]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1866863002/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1866863002/1

[commit-bot: I haz the power, 2016-04-07 02:39:54]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-04-07 02:41:13]

Description was changed from

==========
Reland: Move glyph lookup to hb-ot-font and remove glyph cache in HarfBuzzFace

Relanding after previously reverted because it caused linkage issues
for chromeos=1 developer builds in Linux. These should be addressed
now through dpranke@'s fixes in issue 589342.

Together with Behdad we identified several ways to optimize and cleanup
HarfBuzzFace:
* We moved the glyph lookup completely to the built-in HarfBuzz
  implementation in hb-ot-font.
* This allows us to remove the unbounded glyph cache we kept around in
  HarfBuzzFace.
* We also moved instantantion and ownership of HarfBuzzFontData to
  HarfBuzzFace. We only update the size and unicode-range on each call
  to getScaledFont(), saving us as the allocation and setup costs of
  this object for each shaping call.
* We removed the unneeded callback for retrieving the horizontal origin,
  which was implemented as a noop.

In local measurements on Mac this leads to large improvements in the
blink_perf.layout tests, especially in
chapter-reflow-once-random (>130%), flexbox-lots-of-data (>58%) and
ArabicLineLayout (>26%) with only a few of the microbenchmarks being
slightly slower: So this is an improvement for layout cases that do not
profit much from the word cache.

TBR'ing since this has previously been LGTMed in 
https://codereview.chromium.org/1733193002

BUG=589340
TBR=eae,behdad,kojii
==========

to

==========
Reland: Move glyph lookup to hb-ot-font and remove glyph cache in HarfBuzzFace

Relanding after previously reverted because it caused linkage issues
for chromeos=1 developer builds in Linux. These should be addressed
now through dpranke@'s fixes in issue 589342.

Together with Behdad we identified several ways to optimize and cleanup
HarfBuzzFace:
* We moved the glyph lookup completely to the built-in HarfBuzz
  implementation in hb-ot-font.
* This allows us to remove the unbounded glyph cache we kept around in
  HarfBuzzFace.
* We also moved instantantion and ownership of HarfBuzzFontData to
  HarfBuzzFace. We only update the size and unicode-range on each call
  to getScaledFont(), saving us as the allocation and setup costs of
  this object for each shaping call.
* We removed the unneeded callback for retrieving the horizontal origin,
  which was implemented as a noop.

In local measurements on Mac this leads to large improvements in the
blink_perf.layout tests, especially in
chapter-reflow-once-random (>130%), flexbox-lots-of-data (>58%) and
ArabicLineLayout (>26%) with only a few of the microbenchmarks being
slightly slower: So this is an improvement for layout cases that do not
profit much from the word cache.

TBR'ing since this has previously been LGTMed in
https://codereview.chromium.org/1733193002

BUG=589340
TBR=eae,behdad,kojii

Committed: https://crrev.com/b2a8582e83ef3022ac1cc65648348dfd168b77cd
Cr-Commit-Position: refs/heads/master@{#385631}
==========

[commit-bot: I haz the power, 2016-04-07 02:41:15]

Patchset 1 (id:??) landed as
https://crrev.com/b2a8582e83ef3022ac1cc65648348dfd168b77cd
Cr-Commit-Position: refs/heads/master@{#385631}