Use FontFallbackPriority Fonts in FontFallbackIterator

Use FontFallbackPriority Fonts in FontFallbackIterator

Now that the pieces are in place, use the emoji and symbol fonts in
FontFallbackIterator. Previously FontCache's character fallback
functions were extended so that they take FontFallbackPriority into
account. These functions can now be used in FontFallbackIterator as a
fallback priority stage where those fonts are used as the first fallback
font in order to correctly distinguish between emoji and text
presentation emoji.

BUG=549571
R=eae, behdad

Committed: https://crrev.com/978d4a1ba3d9654905378de192e64f9232e62798
Cr-Commit-Position: refs/heads/master@{#379036}

[drott, 2016-02-05 11:49:53]

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

[commit-bot: I haz the power, 2016-02-05 11:50:13]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1672553004/1
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1672553004/1

[drott, 2016-02-05 11:55:41]

Column limit

[drott, 2016-02-05 11:55:48]

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

[commit-bot: I haz the power, 2016-02-05 11:56:19]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1672553004/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1672553004/20001

[commit-bot: I haz the power, 2016-02-05 13:15:39]

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

[commit-bot: I haz the power, 2016-02-05 13:15:40]

Dry run: Try jobs failed on following builders:
  win_chromium_rel_ng on tryserver.chromium.win (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.win/builders/win_chromium_rel_...)

[drott, 2016-02-05 13:29:18]

https://codereview.chromium.org/1672553004/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/platform/fonts/FontFallbackIterator.cpp (right):

https://codereview.chromium.org/1672553004/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/platform/fonts/FontFallbackIterator.cpp:37: //
Currently we have to push the Emoji font to the top of the list
Looks like the windows failures indicate there is still some work required.
Overriding the font stack for symbols and math leads to unexpected results. So
it's better to address this issue first, then inserting the emoji and symbol
fonts before the system fonts in the fallback chain, but not before the CSS font
group fonts.

[eae, 2016-02-08 08:20:18]

I'd like behdad to comment on the general approach before doing a detailed
review but overall this looks great to me.

[behdad, 2016-02-17 12:11:11]

lgtm

[eae, 2016-02-17 18:55:17]

LGTM w/comments

https://codereview.chromium.org/1672553004/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/platform/fonts/FontDataRange.h (right):

https://codereview.chromium.org/1672553004/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/platform/fonts/FontDataRange.h:65: bool isNull() const
{ return !fontData(); }
hasData or isEmpty would be better names. isNull would indicate that the struct
itself is null.

https://codereview.chromium.org/1672553004/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/platform/fonts/FontFallbackIterator.cpp (right):

https://codereview.chromium.org/1672553004/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/platform/fonts/FontFallbackIterator.cpp:40: ?
FallbackPriorityFonts
Indent line 40 and 41 one more level.

isNonTextFallbackPriority(fontFallbackPriority)
  ? FallbackPriorityFonts
  : FontGroupFonts

[drott, 2016-03-02 15:29:23]

Description was changed from

==========
Use FontFallbackPriority Fonts in FontFallbackIterator

Now that the pieces are in place, use the emoji and symbol fonts in
FontFallbackIterator. After 49d9c1f5fc97e FontCache provides an API for
retrieving dedicated fonts for Emoji in text and emoji presentation,
math and symbols. These can now be used in FontFallbackIterator as a
priority stage where those fonts are used first in order to correctly
distinguish between emoji and text presentaiton emoji and improve
rendering of other symbol characters.

We can currently only activate this on all platforms except Android,
since we need to find a way to explicitly select the right fonts on this
platform, compare crbug.com/322658.

BUG=549571
R=eae, behdad
==========

to

==========
Use FontFallbackPriority Fonts in FontFallbackIterator

Now that the pieces are in place, use the emoji and symbol fonts in
FontFallbackIterator. Previously FontCache's character fallback
functions were extended so that they take FontFallbackPriority into
account. These functions can now be used in FontFallbackIterator as a
fallback priority stage where those fonts are used as the first fallback
font in order to correctly distinguish between emoji and text
presentation emoji.

BUG=549571
R=eae, behdad
==========

[drott, 2016-03-02 16:37:53]

Review feedback addressed, this CL now depends on the updated version of the
FontCache API in https://codereview.chromium.org/1757703003/

[eae, 2016-03-02 18:27:13]

LGTM

[drott, 2016-03-03 05:33:13]

The CQ bit was checked by drott@chromium.org

[drott, 2016-03-03 05:33:14]

The patchset sent to the CQ was uploaded after l-g-t-m from behdad@chromium.org
Link to the patchset: https://codereview.chromium.org/1672553004/#ps40001
(title: "Major changes to adapt to new version of fallback API")

[commit-bot: I haz the power, 2016-03-03 05:33:32]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1672553004/40001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1672553004/40001

[commit-bot: I haz the power, 2016-03-03 07:01:07]

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

[commit-bot: I haz the power, 2016-03-03 07:01:08]

Try jobs failed on following builders:
  mac_chromium_rel_ng on tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[drott, 2016-03-03 08:43:28]

TestExpectations update, more emoji shown

[drott, 2016-03-03 12:53:56]

The CQ bit was checked by drott@chromium.org

[drott, 2016-03-03 12:53:58]

The patchset sent to the CQ was uploaded after l-g-t-m from eae@chromium.org,
behdad@chromium.org
Link to the patchset: https://codereview.chromium.org/1672553004/#ps60001
(title: "TestExpectations update, more emoji shown")

[commit-bot: I haz the power, 2016-03-03 12:54:11]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1672553004/60001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1672553004/60001

[commit-bot: I haz the power, 2016-03-03 12:54:13]

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

[commit-bot: I haz the power, 2016-03-03 12:54:14]

CLs for remote refs other than refs/pending/heads/master must contain NOTRY=true
and NOPRESUBMIT=true in order for the CQ to process them

[drott, 2016-03-03 13:51:11]

target branch changed

[drott, 2016-03-03 13:51:20]

The CQ bit was checked by drott@chromium.org

[drott, 2016-03-03 13:51:20]

The patchset sent to the CQ was uploaded after l-g-t-m from eae@chromium.org,
behdad@chromium.org
Link to the patchset: https://codereview.chromium.org/1672553004/#ps80001
(title: "target branch changed")

[commit-bot: I haz the power, 2016-03-03 13:51:25]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1672553004/80001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1672553004/80001

[drott, 2016-03-03 16:56:04]

win rebaselines for emoji related test

[drott, 2016-03-03 16:56:23]

The CQ bit was checked by drott@chromium.org

[drott, 2016-03-03 16:56:23]

The patchset sent to the CQ was uploaded after l-g-t-m from eae@chromium.org,
behdad@chromium.org
Link to the patchset: https://codereview.chromium.org/1672553004/#ps100001
(title: "win rebaselines for emoji related test")

[commit-bot: I haz the power, 2016-03-03 16:56:47]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1672553004/100001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1672553004/100001

[commit-bot: I haz the power, 2016-03-03 18:06:52]

Committed patchset #6 (id:100001)

[commit-bot: I haz the power, 2016-03-03 18:07:47]

Description was changed from

==========
Use FontFallbackPriority Fonts in FontFallbackIterator

Now that the pieces are in place, use the emoji and symbol fonts in
FontFallbackIterator. Previously FontCache's character fallback
functions were extended so that they take FontFallbackPriority into
account. These functions can now be used in FontFallbackIterator as a
fallback priority stage where those fonts are used as the first fallback
font in order to correctly distinguish between emoji and text
presentation emoji.

BUG=549571
R=eae, behdad
==========

to

==========
Use FontFallbackPriority Fonts in FontFallbackIterator

Now that the pieces are in place, use the emoji and symbol fonts in
FontFallbackIterator. Previously FontCache's character fallback
functions were extended so that they take FontFallbackPriority into
account. These functions can now be used in FontFallbackIterator as a
fallback priority stage where those fonts are used as the first fallback
font in order to correctly distinguish between emoji and text
presentation emoji.

BUG=549571
R=eae, behdad

Committed: https://crrev.com/978d4a1ba3d9654905378de192e64f9232e62798
Cr-Commit-Position: refs/heads/master@{#379036}
==========

[commit-bot: I haz the power, 2016-03-03 18:07:49]

Patchset 6 (id:??) landed as
https://crrev.com/978d4a1ba3d9654905378de192e64f9232e62798
Cr-Commit-Position: refs/heads/master@{#379036}

[Dmitry Titov, 2016-03-03 19:45:33]

A revert of this CL (patchset #6 id:100001) has been created in
https://codereview.chromium.org/1758383002/ by dimich@chromium.org.

The reason for reverting is: Broke layout tests:
https://build.chromium.org/p/chromium.webkit/builders/WebKit%20Win10/builds/7227

See http://crbug.com/591778.