Fix typeface ids on Mac.

Fix typeface ids on Mac.

The current typeface ids with CoreText rely on ATS (which causes
memory use issues) or font data (which is unreliable, and will not
work with axes and synthetics). This changes the code so that stream
fonts never end up in the cache and always get a unique id, and
system fonts will be given an id as they are used.

Committed: https://skia.googlesource.com/skia/+/64fb51d36df5d4e857c3425fe4cb1b1ecbd169fb

[bungeman-skia, 2015-05-04 18:34:05]

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

[bungeman-skia, 2015-05-04 18:34:06]

https://codereview.chromium.org/1125763002/diff/1/src/ports/SkFontHost_mac.cpp
File src/ports/SkFontHost_mac.cpp (left):

https://codereview.chromium.org/1125763002/diff/1/src/ports/SkFontHost_mac.cp...
src/ports/SkFontHost_mac.cpp:416: ATSFontRef ats =
CTFontGetPlatformFont(fontRef, NULL);
This is known to cause a separate copy of the font to be created in memory,
doesn't exist on iOS, and is deprecated and may not work how you think it works.

https://codereview.chromium.org/1125763002/diff/1/src/ports/SkFontHost_mac.cp...
src/ports/SkFontHost_mac.cpp:574: face->ref();
This is a race. FindByID doesn't ref what it returns, on the assumption that if
you're calling it you already have the typeface in question and you're just
checking to see if it's already in the cache. However, we don't here.

https://codereview.chromium.org/1125763002/diff/1/src/ports/SkFontHost_mac.cp...
src/ports/SkFontHost_mac.cpp:2086: AutoCFRelease<CFDictionaryRef>
fontFamilyNameDictionary(
This block of code does not appear to help us in any way. It set the requested
name on the CTFont itself, but we never actually look there (we pass the
requested name as skFamilyName below, which is what is later used by
find_by_NameStyle above to match).

[reed1, 2015-05-04 18:36:42]

lgtm

[bungeman-skia, 2015-05-04 18:37:21]

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

[commit-bot: I haz the power, 2015-05-04 18:37:35]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1125763002/20001

[commit-bot: I haz the power, 2015-05-04 18:43:02]

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

[commit-bot: I haz the power, 2015-05-04 18:43:04]

Dry run: This issue passed the CQ dry run.

[bungeman-skia, 2015-05-04 19:03:19]

The CQ bit was checked by bungeman@google.com

[commit-bot: I haz the power, 2015-05-04 19:03:41]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1125763002/20001

[commit-bot: I haz the power, 2015-05-04 19:03:56]

Committed patchset #2 (id:20001) as
https://skia.googlesource.com/skia/+/64fb51d36df5d4e857c3425fe4cb1b1ecbd169fb