aura: Switch to light hinting for UI text.
aura: Switch to light hinting for UI text.

The eternal debate continues...

This makes us use light hinting instead of strong hinting
for Pango-Cairo-rendered text in the UI (including the tab
strip and the wrench menu), which improves the shaping of
glyphs like 'B' and 'T'.  On the other hand, it makes color
fringes more noticeable, although the effect is worse on e.g.
my Dell 2405FPW than on Lumpy.  I believe that the long-term
plan is to instead draw this text using Skia and improve
subpixel rendering there.

The change also has the added-but-unintended benefit of
fixing some off-by-one misplacement of glyphs in the omnibox
that I believe we picked up when we switched from GTK+ to
Aura Views.

(I tried medium hinting as well, but it's identical to strong
hinting.)

For before-and-after, see
http://www/~derat/no_crawl/20120309/tabs.png and
http://www/~derat/no_crawl/20120309/menu.png.

BUG=116296,117268
TEST=manual inspection on lumpy

Review URL: http://codereview.chromium.org/9664007

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@125906 0039d316-1c4b-4281-b951-d872f2087c98

junmin-zhu/chromium-rivertrail,krieger-od/nwjs_chromium.src,bright-sparks/chromium-spacewalk,crosswalk-project/chromium-crosswalk-efl,keishi/chromium,rogerwang/chromium,Fireblend/chromium-crosswalk,Chilledheart/chromium,nacl-webkit/chrome_deps,TheTypoMaster/chromium-crosswalk,Jonekee/chromium.src,robclark/chromium,dushu1203/chromium.src,axinging/chromium-crosswalk,patrickm/chromium.src,anirudhSK/chromium,Fireblend/chromium-crosswalk,pozdnyakov/chromium-crosswalk,Pluto-tv/chromium-crosswalk,junmin-zhu/chromium-rivertrail,TheTypoMaster/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,axinging/chromium-crosswalk,chuan9/chromium-crosswalk,pozdnyakov/chromium-crosswalk,crosswalk-project/chromium-crosswalk-efl,littlstar/chromium.src,hgl888/chromium-crosswalk,rogerwang/chromium,dushu1203/chromium.src,dednal/chromium.src,junmin-zhu/chromium-rivertrail,pozdnyakov/chromium-crosswalk,zcbenz/cefode-chromium,robclark/chromium,ChromiumWebApps/chromium,keishi/chromium,axinging/chromium-crosswalk,hujiajie/pa-chromium,ChromiumWebApps/chromium,pozdnyakov/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,M4sse/chromium.src,krieger-od/nwjs_chromium.src,crosswalk-project/chromium-crosswalk-efl,nacl-webkit/chrome_deps,Chilledheart/chromium,rogerwang/chromium,fujunwei/chromium-crosswalk,ondra-novak/chromium.src,timopulkkinen/BubbleFish,axinging/chromium-crosswalk,Just-D/chromium-1,fujunwei/chromium-crosswalk,Chilledheart/chromium,ChromiumWebApps/chromium,axinging/chromium-crosswalk,Jonekee/chromium.src,robclark/chromium,chuan9/chromium-crosswalk,ChromiumWebApps/chromium,Just-D/chromium-1,M4sse/chromium.src,hgl888/chromium-crosswalk-efl,anirudhSK/chromium,markYoungH/chromium.src,junmin-zhu/chromium-rivertrail,mogoweb/chromium-crosswalk,dushu1203/chromium.src,littlstar/chromium.src,mogoweb/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,littlstar/chromium.src,robclark/chromium,rogerwang/chromium,keishi/chromium,crosswalk-project/chromium-crosswalk-efl,mohamed--abdel-maksoud/chromium.src,markYoungH/chromium.src,ltilve/chromium,Chilledheart/chromium,zcbenz/cefode-chromium,hgl888/chromium-crosswalk,Pluto-tv/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,chuan9/chromium-crosswalk,pozdnyakov/chromium-crosswalk,mogoweb/chromium-crosswalk,ltilve/chromium,hujiajie/pa-chromium,anirudhSK/chromium,Fireblend/chromium-crosswalk,fujunwei/chromium-crosswalk,junmin-zhu/chromium-rivertrail,bright-sparks/chromium-spacewalk,jaruba/chromium.src,ondra-novak/chromium.src,dushu1203/chromium.src,TheTypoMaster/chromium-crosswalk,zcbenz/cefode-chromium,robclark/chromium,dednal/chromium.src,mogoweb/chromium-crosswalk,markYoungH/chromium.src,ondra-novak/chromium.src,Jonekee/chromium.src,mogoweb/chromium-crosswalk,junmin-zhu/chromium-rivertrail,Jonekee/chromium.src,Fireblend/chromium-crosswalk,patrickm/chromium.src,TheTypoMaster/chromium-crosswalk,mogoweb/chromium-crosswalk,M4sse/chromium.src,jaruba/chromium.src,hgl888/chromium-crosswalk-efl,ltilve/chromium,PeterWangIntel/chromium-crosswalk,axinging/chromium-crosswalk,dushu1203/chromium.src,hujiajie/pa-chromium,mohamed--abdel-maksoud/chromium.src,hujiajie/pa-chromium,ondra-novak/chromium.src,dushu1203/chromium.src,hujiajie/pa-chromium,zcbenz/cefode-chromium,M4sse/chromium.src,robclark/chromium,TheTypoMaster/chromium-crosswalk,ltilve/chromium,Fireblend/chromium-crosswalk,ltilve/chromium,hujiajie/pa-chromium,crosswalk-project/chromium-crosswalk-efl,ltilve/chromium,Pluto-tv/chromium-crosswalk,jaruba/chromium.src,hgl888/chromium-crosswalk-efl,Fireblend/chromium-crosswalk,Jonekee/chromium.src,chuan9/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,ChromiumWebApps/chromium,markYoungH/chromium.src,hujiajie/pa-chromium,krieger-od/nwjs_chromium.src,markYoungH/chromium.src,bright-sparks/chromium-spacewalk,mohamed--abdel-maksoud/chromium.src,dednal/chromium.src,Jonekee/chromium.src,keishi/chromium,zcbenz/cefode-chromium,timopulkkinen/BubbleFish,markYoungH/chromium.src,bright-sparks/chromium-spacewalk,zcbenz/cefode-chromium,pozdnyakov/chromium-crosswalk,dushu1203/chromium.src,pozdnyakov/chromium-crosswalk,littlstar/chromium.src,fujunwei/chromium-crosswalk,dednal/chromium.src,mogoweb/chromium-crosswalk,bright-sparks/chromium-spacewalk,M4sse/chromium.src,rogerwang/chromium,bright-sparks/chromium-spacewalk,Just-D/chromium-1,crosswalk-project/chromium-crosswalk-efl,jaruba/chromium.src,mohamed--abdel-maksoud/chromium.src,patrickm/chromium.src,Pluto-tv/chromium-crosswalk,zcbenz/cefode-chromium,M4sse/chromium.src,hujiajie/pa-chromium,timopulkkinen/BubbleFish,keishi/chromium,ondra-novak/chromium.src,Jonekee/chromium.src,crosswalk-project/chromium-crosswalk-efl,robclark/chromium,jaruba/chromium.src,mohamed--abdel-maksoud/chromium.src,Just-D/chromium-1,krieger-od/nwjs_chromium.src,timopulkkinen/BubbleFish,ltilve/chromium,ondra-novak/chromium.src,timopulkkinen/BubbleFish,fujunwei/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,krieger-od/nwjs_chromium.src,TheTypoMaster/chromium-crosswalk,Chilledheart/chromium,rogerwang/chromium,junmin-zhu/chromium-rivertrail,jaruba/chromium.src,hgl888/chromium-crosswalk,krieger-od/nwjs_chromium.src,axinging/chromium-crosswalk,timopulkkinen/BubbleFish,rogerwang/chromium,Chilledheart/chromium,Jonekee/chromium.src,keishi/chromium,nacl-webkit/chrome_deps,Chilledheart/chromium,anirudhSK/chromium,mohamed--abdel-maksoud/chromium.src,zcbenz/cefode-chromium,markYoungH/chromium.src,dednal/chromium.src,axinging/chromium-crosswalk,dednal/chromium.src,dushu1203/chromium.src,hujiajie/pa-chromium,zcbenz/cefode-chromium,littlstar/chromium.src,axinging/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,junmin-zhu/chromium-rivertrail,dednal/chromium.src,PeterWangIntel/chromium-crosswalk,Pluto-tv/chromium-crosswalk,robclark/chromium,junmin-zhu/chromium-rivertrail,jaruba/chromium.src,markYoungH/chromium.src,mohamed--abdel-maksoud/chromium.src,ChromiumWebApps/chromium,M4sse/chromium.src,hgl888/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,ChromiumWebApps/chromium,jaruba/chromium.src,rogerwang/chromium,zcbenz/cefode-chromium,Jonekee/chromium.src,markYoungH/chromium.src,M4sse/chromium.src,ChromiumWebApps/chromium,Pluto-tv/chromium-crosswalk,axinging/chromium-crosswalk,rogerwang/chromium,timopulkkinen/BubbleFish,nacl-webkit/chrome_deps,mogoweb/chromium-crosswalk,ltilve/chromium,mohamed--abdel-maksoud/chromium.src,Jonekee/chromium.src,hgl888/chromium-crosswalk-efl,hgl888/chromium-crosswalk,jaruba/chromium.src,markYoungH/chromium.src,bright-sparks/chromium-spacewalk,dednal/chromium.src,robclark/chromium,hgl888/chromium-crosswalk,ChromiumWebApps/chromium,hgl888/chromium-crosswalk-efl,ChromiumWebApps/chromium,hgl888/chromium-crosswalk-efl,nacl-webkit/chrome_deps,littlstar/chromium.src,anirudhSK/chromium,krieger-od/nwjs_chromium.src,Jonekee/chromium.src,chuan9/chromium-crosswalk,timopulkkinen/BubbleFish,mohamed--abdel-maksoud/chromium.src,dushu1203/chromium.src,Just-D/chromium-1,chuan9/chromium-crosswalk,krieger-od/nwjs_chromium.src,pozdnyakov/chromium-crosswalk,bright-sparks/chromium-spacewalk,markYoungH/chromium.src,Just-D/chromium-1,nacl-webkit/chrome_deps,mogoweb/chromium-crosswalk,M4sse/chromium.src,nacl-webkit/chrome_deps,krieger-od/nwjs_chromium.src,keishi/chromium,ChromiumWebApps/chromium,dednal/chromium.src,jaruba/chromium.src,ondra-novak/chromium.src,patrickm/chromium.src,pozdnyakov/chromium-crosswalk,anirudhSK/chromium,fujunwei/chromium-crosswalk,chuan9/chromium-crosswalk,nacl-webkit/chrome_deps,junmin-zhu/chromium-rivertrail,ChromiumWebApps/chromium,nacl-webkit/chrome_deps,patrickm/chromium.src,dushu1203/chromium.src,anirudhSK/chromium,Just-D/chromium-1,axinging/chromium-crosswalk,zcbenz/cefode-chromium,chuan9/chromium-crosswalk,keishi/chromium,keishi/chromium,pozdnyakov/chromium-crosswalk,anirudhSK/chromium,keishi/chromium,timopulkkinen/BubbleFish,Chilledheart/chromium,hgl888/chromium-crosswalk-efl,ondra-novak/chromium.src,M4sse/chromium.src,fujunwei/chromium-crosswalk,dednal/chromium.src,Pluto-tv/chromium-crosswalk,crosswalk-project/chromium-crosswalk-efl,hujiajie/pa-chromium,fujunwei/chromium-crosswalk,hgl888/chromium-crosswalk,bright-sparks/chromium-spacewalk,mogoweb/chromium-crosswalk,patrickm/chromium.src,Pluto-tv/chromium-crosswalk,Fireblend/chromium-crosswalk,Fireblend/chromium-crosswalk,Chilledheart/chromium,Just-D/chromium-1,hgl888/chromium-crosswalk,nacl-webkit/chrome_deps,hujiajie/pa-chromium,Pluto-tv/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,Just-D/chromium-1,anirudhSK/chromium,junmin-zhu/chromium-rivertrail,littlstar/chromium.src,ondra-novak/chromium.src,littlstar/chromium.src,keishi/chromium,robclark/chromium,ltilve/chromium,crosswalk-project/chromium-crosswalk-efl,hgl888/chromium-crosswalk-efl,dednal/chromium.src,Fireblend/chromium-crosswalk,pozdnyakov/chromium-crosswalk,patrickm/chromium.src,krieger-od/nwjs_chromium.src,nacl-webkit/chrome_deps,chuan9/chromium-crosswalk,patrickm/chromium.src,dushu1203/chromium.src,patrickm/chromium.src,jaruba/chromium.src,fujunwei/chromium-crosswalk,timopulkkinen/BubbleFish,anirudhSK/chromium,hgl888/chromium-crosswalk-efl,hgl888/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,anirudhSK/chromium,krieger-od/nwjs_chromium.src,rogerwang/chromium,mohamed--abdel-maksoud/chromium.src,M4sse/chromium.src,hgl888/chromium-crosswalk-efl,anirudhSK/chromium,PeterWangIntel/chromium-crosswalk,timopulkkinen/BubbleFish