gcapi mac: If a system ticket points to a nonexistent folder, also set 'access denied'.
gcapi mac: If a system ticket points to a nonexistent folder, also set 'access denied'.

That way, installers can opt to not call LaunchGoogleChrome() for
system installs.

Also add a few null checks if getting the effective user fails.

BUG=none

Review URL: https://codereview.chromium.org/11308079

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@168329 0039d316-1c4b-4281-b951-d872f2087c98

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