Linux: add LOG(FATAL) to try and catch an error.
Linux: add LOG(FATAL) to try and catch an error.

Crash reports like:
  http://crash/reportview?product=Chrome_Linux&version=3.0.192.0&date=&signature=WebCore::TextRunWalker::nextScriptRun()-3F2080B

are popping up and I don't know why. I suspect that we might we
returning an empty family string from fontconfig, so I'm adding a
LOG(FATAL) to catch this. We'll see in the crash reports from next
week if it's getting hit.

R=evan


git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@20271 0039d316-1c4b-4281-b951-d872f2087c98

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