Argh, reverting the change to remove the "crx" file extension hack in DownloadManager.
Argh, reverting the change to remove the "crx" file extension
hack in DownloadManager.

For those playing along at home, this change makes it so that
we once again consider any file that ends in ".crx" an
extension.

The problem is that file:// URLs are not-sniffable, so with
this change we cannot install extensions from file:// URLs.

We need to fix things so that we consider file associations
for local files, I guess.

TBR=mpcomplete@chromium.org

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@23362 0039d316-1c4b-4281-b951-d872f2087c98

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