Fix crash in browserAction.setIcon
Fix crash in browserAction.setIcon

Crash occurs when icon we set is empty.

BUG=142908
TEST=manual

NOTE: I'll add test for this later.


Review URL: https://chromiumcodereview.appspot.com/10824314

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@151776 0039d316-1c4b-4281-b951-d872f2087c98

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