GTTF: Replace DCHECK with EXPECT_TRUE in UITestBase.
GTTF: Replace DCHECK with EXPECT_TRUE in UITestBase.

We should avoid crashing entire ui_tests in case of failure.
With EXPECT_TRUE we still see it, but tests continue to run.

TBR=huanr

Review URL: http://codereview.chromium.org/2868116

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@55279 0039d316-1c4b-4281-b951-d872f2087c98

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