aura-x11: Make sure the list of devices to track are updated when device hierarchy changes, and turn XInput2 back on.
aura-x11: Make sure the list of devices to track are updated when device hierarchy changes, and turn XInput2 back on.

If a device gets initialized after chrome boots up, then it is necessary to
update the list of devices chrome accepts input-events from.

BUG=106516
TEST=manually


Review URL: http://codereview.chromium.org/8892005

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@114601 0039d316-1c4b-4281-b951-d872f2087c98

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