Compile with VS2015.

Compile with VS2015.

Visual Studio 2015 has additional warnings around noexcept and
disabling exceptions, which can be worked around with the
(undocumented) _HAS_EXCEPTIONS macro.

Visual Studio 2013 and 2015 have roundf in math.h, so use it to
avoid extra work and casts.

We avoid using cmath, as it undefs isfinite on gcc, but Visual Studio
2015 no longer provides overloads of copysign from math.h (which is
actually correct). As a result, use copysignf (which is available in
math.h in 2013 and 2015) directly.

Committed: https://skia.googlesource.com/skia/+/b7069e9c1f65d11f9581be0adbffa968257afc33

[bungeman-skia, 2015-07-21 20:57:50]

The CQ bit was checked by bungeman@google.com to run a CQ dry run

[commit-bot: I haz the power, 2015-07-21 20:57:58]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1244173005/1

[commit-bot: I haz the power, 2015-07-21 21:05:14]

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

[commit-bot: I haz the power, 2015-07-21 21:05:14]

Dry run: This issue passed the CQ dry run.

[bungeman-skia, 2015-07-21 21:07:27]

bungeman@google.com changed reviewers:
+ bsalomon@google.com, mtklein@google.com

[bungeman-skia, 2015-07-21 21:07:28]

I went and installed Visual Studio 2015 to see what the damage is. Isn't all
that bad as far as I can tell.

https://codereview.chromium.org/1244173005/diff/1/gyp/common_conditions.gypi
File gyp/common_conditions.gypi (right):

https://codereview.chromium.org/1244173005/diff/1/gyp/common_conditions.gypi#...
gyp/common_conditions.gypi:49: '_HAS_EXCEPTIONS=0',
This is used by the standard library, and seems like the right thing to do since
we're setting 'ExceptionHandling: '0' a few lines down (line 62). The
alternative is to suppress at least one warning about noexcept, but there may be
more.

[mtklein, 2015-07-21 21:10:38]

lgtm

[bsalomon, 2015-07-21 21:11:41]

lgtm

[bungeman-skia, 2015-07-21 21:13:37]

The CQ bit was checked by bungeman@google.com

[commit-bot: I haz the power, 2015-07-21 21:13:57]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1244173005/1

[commit-bot: I haz the power, 2015-07-21 21:14:33]

Committed patchset #1 (id:1) as
https://skia.googlesource.com/skia/+/b7069e9c1f65d11f9581be0adbffa968257afc33