Avoid RefPtr cycle between FontPlatformData and HarfBuzzFace

Avoid RefPtr cycle between FontPlatformData and HarfBuzzFace

When retrieving getScaledFont() from HarfBuzzFace we were creating a
SimpleFontData and assigning it to the HarfBuzzFontData object that is
kept as the user data pointer for HarfBuzz callbacks. This introduces a
reference counting cycle since SimpleFontData owns the FontPlatformData
it was created from, and harfBuzzFace() is retrieved from
FontPlatformData itself.

Since getScaledFont() is called on a HarfBuzzFace instance that is
retrieved from FontPlatformData and only used for one shaping iteration,
reducing the link to SimpleFontData to a non owning pointer should be
acceptable.

BUG=617637
R=eae,tzik,kojii

Committed: https://crrev.com/b6d1c182819aece33f03b138092445440d2f0adf
Cr-Commit-Position: refs/heads/master@{#398059}

[drott, 2016-06-06 16:05:53]

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

[commit-bot: I haz the power, 2016-06-06 16:06:09]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2039263002/1

[eae, 2016-06-06 17:29:44]

Yay!

LGTM

[eae, 2016-06-06 17:32:05]

The CQ bit was unchecked by eae@chromium.org

[eae, 2016-06-06 17:32:10]

The CQ bit was checked by eae@chromium.org

[commit-bot: I haz the power, 2016-06-06 17:32:53]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/2039263002/1

[commit-bot: I haz the power, 2016-06-06 17:51:47]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-06-06 17:54:00]

Description was changed from

==========
Avoid RefPtr cycle between FontPlatformData and HarfBuzzFace

When retrieving getScaledFont() from HarfBuzzFace we were creating a
SimpleFontData and assigning it to the HarfBuzzFontData object that is
kept as the user data pointer for HarfBuzz callbacks. This introduces a
reference counting cycle since SimpleFontData owns the FontPlatformData
it was created from, and harfBuzzFace() is retrieved from
FontPlatformData itself.

Since getScaledFont() is called on a HarfBuzzFace instance that is
retrieved from FontPlatformData and only used for one shaping iteration,
reducing the link to SimpleFontData to a non owning pointer should be
acceptable.

BUG=617637
R=eae,tzik,kojii
==========

to

==========
Avoid RefPtr cycle between FontPlatformData and HarfBuzzFace

When retrieving getScaledFont() from HarfBuzzFace we were creating a
SimpleFontData and assigning it to the HarfBuzzFontData object that is
kept as the user data pointer for HarfBuzz callbacks. This introduces a
reference counting cycle since SimpleFontData owns the FontPlatformData
it was created from, and harfBuzzFace() is retrieved from
FontPlatformData itself.

Since getScaledFont() is called on a HarfBuzzFace instance that is
retrieved from FontPlatformData and only used for one shaping iteration,
reducing the link to SimpleFontData to a non owning pointer should be
acceptable.

BUG=617637
R=eae,tzik,kojii

Committed: https://crrev.com/b6d1c182819aece33f03b138092445440d2f0adf
Cr-Commit-Position: refs/heads/master@{#398059}
==========

[commit-bot: I haz the power, 2016-06-06 17:54:01]

Patchset 1 (id:??) landed as
https://crrev.com/b6d1c182819aece33f03b138092445440d2f0adf
Cr-Commit-Position: refs/heads/master@{#398059}