Try last resort on no-match in platformFallbackForCharacter on Android

Try last resort on no-match in platformFallbackForCharacter on Android

On Android, some locale-preferred fonts (e.g. DroidSansFallback.ttf for
Chinese locale) doesn't contain all characters that the default locale
system fonts contain.

For characters that is missing in the font, fallback to the default
locale system font, by calling getLastResortFallbackFont() in
FontCache::platformFallbackForCharacter().

Also modified getLastResortFallbackFont() to prefer Skia default font
instead of the hard-coded default font (sans) and to map also cursive
and fantasy generic families.

Combined similar code in FontCacheSkia.cpp.

BUG=347121
TEST=FontCacheAndroid.platformFallbackForCharacter (will be enabled in another CL)
R=dglazkov@chromium.org

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=168410

[dglazkov, 2014-03-04 05:08:07]

lgtm. How about a unit test?

[Xianzhu, 2014-03-04 18:17:17]

On 2014/03/04 05:08:07, Dimitri Glazkov wrote:
> lgtm. How about a unit test?

Added. However, for now blink_platform_unittests is not built and run on
Android. Will enable it in another change.

[Xianzhu, 2014-03-04 18:17:45]

The CQ bit was checked by wangxianzhu@chromium.org

[commit-bot: I haz the power, 2014-03-04 18:17:52]

CQ is trying da patch. Follow status at
https://chromium-status.appspot.com/cq/wangxianzhu@chromium.org/185863007/20001

[Xianzhu, 2014-03-04 23:30:31]

Committed patchset #2 manually as r168410 (presubmit successful).