PlatformFontMac: Use a default NSFont when an invalid font is passed.

PlatformFontMac: Use a default NSFont when an invalid font is passed.

Currently RenderTextHarfbuzz crashes trying to find fallbacks for an
null font.

Ensuring PlatformFontMac never has a null NSFont is similar to the
approach in PlatformFontLinux (its anon::CreateSkTypeface(..) never
returns null). Having this invariant allows some logic in
PlatformFontMac to be simplified.

BUG=699820
Review-Url: https://codereview.chromium.org/2959913002
Cr-Commit-Position: refs/heads/master@{#483223}
Committed: https://chromium.googlesource.com/chromium/src/+/0f5cbd14b845f2795a87e9caa7e048e2ccf95947

[tapted, 2017-06-27 06:25:28]

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

[commit-bot: I haz the power, 2017-06-27 06:25:35]

Dry run: CQ is trying da patch.

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

[tapted, 2017-06-27 06:26:34]

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

[commit-bot: I haz the power, 2017-06-27 06:26:46]

Dry run: 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, 2017-06-27 06:37:14]

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

[commit-bot: I haz the power, 2017-06-27 06:37:15]

Dry run: Try jobs failed on following builders:
  linux_chromium_tsan_rel_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[tapted, 2017-06-28 01:21:17]

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

[commit-bot: I haz the power, 2017-06-28 01:21:34]

Dry run: CQ is trying da patch.

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

[tapted, 2017-06-28 01:28:01]

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

[commit-bot: I haz the power, 2017-06-28 01:28:24]

Dry run: CQ is trying da patch.

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

[tapted, 2017-06-28 01:34:10]

Patchset #3 (id:40001) has been deleted

[commit-bot: I haz the power, 2017-06-28 01:54:18]

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

[commit-bot: I haz the power, 2017-06-28 01:54:19]

Dry run: This issue passed the CQ dry run.

[tapted, 2017-06-28 03:43:30]

Description was changed from

==========
Mac RenderTextHarfbuzz: Do not crash on invalid fonts

BUG=699820
==========

to

==========
PlatformFontMac: Use a default NSFont when an invalid font is passed.

Currently RenderTextHarfbuzz crashes trying to find fallbacks for an
null font.

Ensuring PlatformFontMac never has a null NSFont is similar to the
approach in PlatformFontLinux (it's anon::CreateSkTypeface(..) never
returns null). Having this invariant allows some logic in
PlatformFontMac to be simplified.

BUG=699820
==========

[tapted, 2017-06-28 03:43:30]

tapted@chromium.org changed reviewers:
+ asvitkine@chromium.org

[tapted, 2017-06-28 03:43:54]

Description was changed from

==========
PlatformFontMac: Use a default NSFont when an invalid font is passed.

Currently RenderTextHarfbuzz crashes trying to find fallbacks for an
null font.

Ensuring PlatformFontMac never has a null NSFont is similar to the
approach in PlatformFontLinux (it's anon::CreateSkTypeface(..) never
returns null). Having this invariant allows some logic in
PlatformFontMac to be simplified.

BUG=699820
==========

to

==========
PlatformFontMac: Use a default NSFont when an invalid font is passed.

Currently RenderTextHarfbuzz crashes trying to find fallbacks for an
null font.

Ensuring PlatformFontMac never has a null NSFont is similar to the
approach in PlatformFontLinux (its anon::CreateSkTypeface(..) never
returns null). Having this invariant allows some logic in
PlatformFontMac to be simplified.

BUG=699820
==========

[tapted, 2017-06-28 03:46:11]

Hi Alexei, please take a look. An alternative in Patchset 1 also gets past the
crash, but I think Patchset 3 is the more robust solution, and consistent with
other platforms.

https://codereview.chromium.org/2959913002/diff/60001/ui/gfx/font_fallback_ma...
File ui/gfx/font_fallback_mac.mm (right):

https://codereview.chromium.org/2959913002/diff/60001/ui/gfx/font_fallback_ma...
ui/gfx/font_fallback_mac.mm:58: const CFIndex fallback_count =
CFArrayGetCount(cascade_list);
Currently it's this line that crashes -- null can't be passed to CFArrayGetCount

[Alexei Svitkine (slow), 2017-06-28 15:13:13]

lgtm

[tapted, 2017-06-29 00:30:01]

The CQ bit was checked by tapted@chromium.org

[commit-bot: I haz the power, 2017-06-29 00:30:21]

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, 2017-06-29 00:35:55]

CQ is committing da patch.

Bot data: {"patchset_id": 60001, "attempt_start_ts": 1498696201349560,
"parent_rev": "10ec458d9fd50ca19fa8502511b42621cc8b68d7", "commit_rev":
"0f5cbd14b845f2795a87e9caa7e048e2ccf95947"}

[commit-bot: I haz the power, 2017-06-29 00:36:10]

Description was changed from

==========
PlatformFontMac: Use a default NSFont when an invalid font is passed.

Currently RenderTextHarfbuzz crashes trying to find fallbacks for an
null font.

Ensuring PlatformFontMac never has a null NSFont is similar to the
approach in PlatformFontLinux (its anon::CreateSkTypeface(..) never
returns null). Having this invariant allows some logic in
PlatformFontMac to be simplified.

BUG=699820
==========

to

==========
PlatformFontMac: Use a default NSFont when an invalid font is passed.

Currently RenderTextHarfbuzz crashes trying to find fallbacks for an
null font.

Ensuring PlatformFontMac never has a null NSFont is similar to the
approach in PlatformFontLinux (its anon::CreateSkTypeface(..) never
returns null). Having this invariant allows some logic in
PlatformFontMac to be simplified.

BUG=699820

Review-Url: https://codereview.chromium.org/2959913002
Cr-Commit-Position: refs/heads/master@{#483223}
Committed:
https://chromium.googlesource.com/chromium/src/+/0f5cbd14b845f2795a87e9caa7e0...
==========

[commit-bot: I haz the power, 2017-06-29 00:36:11]

Committed patchset #3 (id:60001) as
https://chromium.googlesource.com/chromium/src/+/0f5cbd14b845f2795a87e9caa7e0...