Allow the forwarder to recover if the device_forwarder crashes or hangs
Allow the forwarder to recover if the device_forwarder crashes or hangs

I've noticed on the perf bots that if we get a host_forwarder error
because it can't connect to the device, then all subsequent forwarder
operations will fail. Example:
http://build.chromium.org/p/chromium.perf/builders/Android%20Nexus4%20Perf/builds/1163/steps/Sharded%20Perf%20Tests/logs/stdio

This patch fixes that by killing the device forwarder (and ensuring it
isn't initialized) so that it can be re-initialized on the next
attempt.

BUG=294878

Review URL: https://codereview.chromium.org/427353005

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@287105 0039d316-1c4b-4281-b951-d872f2087c98

Fireblend/chromium-crosswalk,dednal/chromium.src,littlstar/chromium.src,fujunwei/chromium-crosswalk,fujunwei/chromium-crosswalk,hgl888/chromium-crosswalk-efl,littlstar/chromium.src,fujunwei/chromium-crosswalk,ondra-novak/chromium.src,crosswalk-project/chromium-crosswalk-efl,mohamed--abdel-maksoud/chromium.src,Fireblend/chromium-crosswalk,M4sse/chromium.src,dushu1203/chromium.src,hgl888/chromium-crosswalk,hgl888/chromium-crosswalk-efl,bright-sparks/chromium-spacewalk,Jonekee/chromium.src,TheTypoMaster/chromium-crosswalk,bright-sparks/chromium-spacewalk,jaruba/chromium.src,dushu1203/chromium.src,Chilledheart/chromium,Chilledheart/chromium,markYoungH/chromium.src,mohamed--abdel-maksoud/chromium.src,littlstar/chromium.src,jaruba/chromium.src,hgl888/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,Pluto-tv/chromium-crosswalk,markYoungH/chromium.src,hgl888/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,jaruba/chromium.src,ltilve/chromium,crosswalk-project/chromium-crosswalk-efl,M4sse/chromium.src,dednal/chromium.src,hgl888/chromium-crosswalk-efl,bright-sparks/chromium-spacewalk,Just-D/chromium-1,crosswalk-project/chromium-crosswalk-efl,markYoungH/chromium.src,hgl888/chromium-crosswalk,ltilve/chromium,PeterWangIntel/chromium-crosswalk,Fireblend/chromium-crosswalk,axinging/chromium-crosswalk,crosswalk-project/chromium-crosswalk-efl,fujunwei/chromium-crosswalk,Fireblend/chromium-crosswalk,ltilve/chromium,ltilve/chromium,M4sse/chromium.src,Jonekee/chromium.src,M4sse/chromium.src,dednal/chromium.src,markYoungH/chromium.src,M4sse/chromium.src,ondra-novak/chromium.src,dednal/chromium.src,Jonekee/chromium.src,krieger-od/nwjs_chromium.src,chuan9/chromium-crosswalk,fujunwei/chromium-crosswalk,crosswalk-project/chromium-crosswalk-efl,jaruba/chromium.src,markYoungH/chromium.src,mohamed--abdel-maksoud/chromium.src,krieger-od/nwjs_chromium.src,PeterWangIntel/chromium-crosswalk,fujunwei/chromium-crosswalk,Just-D/chromium-1,axinging/chromium-crosswalk,littlstar/chromium.src,Just-D/chromium-1,hgl888/chromium-crosswalk-efl,dushu1203/chromium.src,dednal/chromium.src,dednal/chromium.src,Fireblend/chromium-crosswalk,axinging/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,axinging/chromium-crosswalk,M4sse/chromium.src,M4sse/chromium.src,Just-D/chromium-1,Chilledheart/chromium,TheTypoMaster/chromium-crosswalk,Just-D/chromium-1,PeterWangIntel/chromium-crosswalk,dednal/chromium.src,jaruba/chromium.src,krieger-od/nwjs_chromium.src,chuan9/chromium-crosswalk,hgl888/chromium-crosswalk,TheTypoMaster/chromium-crosswalk,PeterWangIntel/chromium-crosswalk,fujunwei/chromium-crosswalk,krieger-od/nwjs_chromium.src,dushu1203/chromium.src,Pluto-tv/chromium-crosswalk,crosswalk-project/chromium-crosswalk-efl,ltilve/chromium,TheTypoMaster/chromium-crosswalk,Jonekee/chromium.src,crosswalk-project/chromium-crosswalk-efl,Fireblend/chromium-crosswalk,Fireblend/chromium-crosswalk,ltilve/chromium,dushu1203/chromium.src,dushu1203/chromium.src,Jonekee/chromium.src,dednal/chromium.src,dushu1203/chromium.src,Chilledheart/chromium,dednal/chromium.src,bright-sparks/chromium-spacewalk,Chilledheart/chromium,Just-D/chromium-1,jaruba/chromium.src,krieger-od/nwjs_chromium.src,M4sse/chromium.src,littlstar/chromium.src,TheTypoMaster/chromium-crosswalk,littlstar/chromium.src,Pluto-tv/chromium-crosswalk,Pluto-tv/chromium-crosswalk,ondra-novak/chromium.src,dushu1203/chromium.src,krieger-od/nwjs_chromium.src,dednal/chromium.src,krieger-od/nwjs_chromium.src,ondra-novak/chromium.src,hgl888/chromium-crosswalk-efl,axinging/chromium-crosswalk,Fireblend/chromium-crosswalk,Jonekee/chromium.src,hgl888/chromium-crosswalk,Pluto-tv/chromium-crosswalk,ondra-novak/chromium.src,mohamed--abdel-maksoud/chromium.src,fujunwei/chromium-crosswalk,M4sse/chromium.src,Chilledheart/chromium,ltilve/chromium,jaruba/chromium.src,ltilve/chromium,chuan9/chromium-crosswalk,Pluto-tv/chromium-crosswalk,dushu1203/chromium.src,PeterWangIntel/chromium-crosswalk,mohamed--abdel-maksoud/chromium.src,hgl888/chromium-crosswalk-efl,jaruba/chromium.src,krieger-od/nwjs_chromium.src,M4sse/chromium.src,ondra-novak/chromium.src,PeterWangIntel/chromium-crosswalk,ondra-novak/chromium.src,hgl888/chromium-crosswalk-efl,chuan9/chromium-crosswalk,ondra-novak/chromium.src,hgl888/chromium-crosswalk-efl,markYoungH/chromium.src,mohamed--abdel-maksoud/chromium.src,bright-sparks/chromium-spacewalk,markYoungH/chromium.src,bright-sparks/chromium-spacewalk,Fireblend/chromium-crosswalk,chuan9/chromium-crosswalk,Just-D/chromium-1,chuan9/chromium-crosswalk,ondra-novak/chromium.src,Pluto-tv/chromium-crosswalk,Jonekee/chromium.src,mohamed--abdel-maksoud/chromium.src,dednal/chromium.src,Chilledheart/chromium,krieger-od/nwjs_chromium.src,chuan9/chromium-crosswalk,fujunwei/chromium-crosswalk,markYoungH/chromium.src,dushu1203/chromium.src,Just-D/chromium-1,Pluto-tv/chromium-crosswalk,chuan9/chromium-crosswalk,Chilledheart/chromium,mohamed--abdel-maksoud/chromium.src,hgl888/chromium-crosswalk-efl,Just-D/chromium-1,axinging/chro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