[Sk4fGradient] Use infinity floats for clamp-mode extreme positions

[Sk4fGradient] Use infinity floats for clamp-mode extreme positions

In clamp mode, we use a couple of synthetic edges that are supposed to
extend to +/- infinity (-inf .. P0 and Pn .. inf).  Currently we use
SK_ScalarMin/Max, but these can be overrun with large/malicious inputs.

Use SK_ScalarInfinity/SK_ScalarNegativeInfinity instead, and tweak
compute_interval_props() to handle inf values gracefully.

BUG=skia:5835
R=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2441733002

Committed: https://skia.googlesource.com/skia/+/8f457591e6a21c240fd2fca56a97281b556ce796

[f(malita), 2016-10-20 18:34:15]

Description was changed from

==========
[Sk4fGradient] Use infinity floats for clamp extreme positions

In clamp mode, we use a couple of synthetic edges that are supposed to
extend to +/- infinity (-inf .. P0 and Pn .. inf).  Currently we use
SK_ScalarMin/Max, but these can be overflowed with large inputs.

Use SK_ScalarInfinity/SK_ScalarNegativeInfinity instead.

BUG=skia:5835
R=reed@google.com
==========

to

==========
[Sk4fGradient] Use infinity floats for clamp extreme positions

In clamp mode, we use a couple of synthetic edges that are supposed to
extend to +/- infinity (-inf .. P0 and Pn .. inf).  Currently we use
SK_ScalarMin/Max, but these can be overflowed with large inputs.

Use SK_ScalarInfinity/SK_ScalarNegativeInfinity instead.

BUG=skia:5835
R=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2441733002
==========

[f(malita), 2016-10-20 21:04:56]

Description was changed from

==========
[Sk4fGradient] Use infinity floats for clamp extreme positions

In clamp mode, we use a couple of synthetic edges that are supposed to
extend to +/- infinity (-inf .. P0 and Pn .. inf).  Currently we use
SK_ScalarMin/Max, but these can be overflowed with large inputs.

Use SK_ScalarInfinity/SK_ScalarNegativeInfinity instead.

BUG=skia:5835
R=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2441733002
==========

to

==========
[Sk4fGradient] Use infinity floats for clamp extreme positions

In clamp mode, we use a couple of synthetic edges that are supposed to
extend to +/- infinity (-inf .. P0 and Pn .. inf).  Currently we use
SK_ScalarMin/Max, but these can be overrun with large/malicious inputs.

Use SK_ScalarInfinity/SK_ScalarNegativeInfinity instead.

BUG=skia:5835
R=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2441733002
==========

[f(malita), 2016-10-20 21:05:28]

Description was changed from

==========
[Sk4fGradient] Use infinity floats for clamp extreme positions

In clamp mode, we use a couple of synthetic edges that are supposed to
extend to +/- infinity (-inf .. P0 and Pn .. inf).  Currently we use
SK_ScalarMin/Max, but these can be overrun with large/malicious inputs.

Use SK_ScalarInfinity/SK_ScalarNegativeInfinity instead.

BUG=skia:5835
R=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2441733002
==========

to

==========
[Sk4fGradient] Use infinity floats for clamp-mode extreme positions

In clamp mode, we use a couple of synthetic edges that are supposed to
extend to +/- infinity (-inf .. P0 and Pn .. inf).  Currently we use
SK_ScalarMin/Max, but these can be overrun with large/malicious inputs.

Use SK_ScalarInfinity/SK_ScalarNegativeInfinity instead.

BUG=skia:5835
R=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2441733002
==========

[f(malita), 2016-10-20 21:07:47]

Description was changed from

==========
[Sk4fGradient] Use infinity floats for clamp-mode extreme positions

In clamp mode, we use a couple of synthetic edges that are supposed to
extend to +/- infinity (-inf .. P0 and Pn .. inf).  Currently we use
SK_ScalarMin/Max, but these can be overrun with large/malicious inputs.

Use SK_ScalarInfinity/SK_ScalarNegativeInfinity instead.

BUG=skia:5835
R=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2441733002
==========

to

==========
[Sk4fGradient] Use infinity floats for clamp-mode extreme positions

In clamp mode, we use a couple of synthetic edges that are supposed to
extend to +/- infinity (-inf .. P0 and Pn .. inf).  Currently we use
SK_ScalarMin/Max, but these can be overrun with large/malicious inputs.

Use SK_ScalarInfinity/SK_ScalarNegativeInfinity instead, and tweak
compute_interval_props() to handle inf values gracefully.

BUG=skia:5835
R=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2441733002
==========

[f(malita), 2016-10-20 21:13:33]

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

[commit-bot: I haz the power, 2016-10-20 21:13:37]

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, 2016-10-20 21:42:48]

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

[commit-bot: I haz the power, 2016-10-20 21:42:49]

Dry run: This issue passed the CQ dry run.

[reed1, 2016-10-21 12:48:45]

lgtm

[f(malita), 2016-10-21 13:00:53]

The CQ bit was checked by fmalita@chromium.org

[commit-bot: I haz the power, 2016-10-21 13:01:03]

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, 2016-10-21 13:02:24]

Description was changed from

==========
[Sk4fGradient] Use infinity floats for clamp-mode extreme positions

In clamp mode, we use a couple of synthetic edges that are supposed to
extend to +/- infinity (-inf .. P0 and Pn .. inf).  Currently we use
SK_ScalarMin/Max, but these can be overrun with large/malicious inputs.

Use SK_ScalarInfinity/SK_ScalarNegativeInfinity instead, and tweak
compute_interval_props() to handle inf values gracefully.

BUG=skia:5835
R=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2441733002
==========

to

==========
[Sk4fGradient] Use infinity floats for clamp-mode extreme positions

In clamp mode, we use a couple of synthetic edges that are supposed to
extend to +/- infinity (-inf .. P0 and Pn .. inf).  Currently we use
SK_ScalarMin/Max, but these can be overrun with large/malicious inputs.

Use SK_ScalarInfinity/SK_ScalarNegativeInfinity instead, and tweak
compute_interval_props() to handle inf values gracefully.

BUG=skia:5835
R=reed@google.com
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2441733002

Committed:
https://skia.googlesource.com/skia/+/8f457591e6a21c240fd2fca56a97281b556ce796
==========

[commit-bot: I haz the power, 2016-10-21 13:02:25]

Committed patchset #4 (id:60001) as
https://skia.googlesource.com/skia/+/8f457591e6a21c240fd2fca56a97281b556ce796