Fix crashing in FFmpegGlueTest.Write and friends
Fix crashing in FFmpegGlueTest.Write and friends

BUG=36037
TEST=FFmpegGlueTest.* runs on build bot

FFmpegGlueTest.Write was crashing on build bots due to that it
has dependencies on previous test to run. And strangely the build bot
didn't run all the test cases, resulting the crash.

This is fixed by extracting the initialization step and putting it
into a common test setup task.

Review URL: http://codereview.chromium.org/668034

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@40800 0039d316-1c4b-4281-b951-d872f2087c98

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