Revert 121165 - Revert 121068 - linux: add a use_gold flag that defaults to on
Revert 121165 - Revert 121068 - linux: add a use_gold flag that defaults to on

[This CL was backed out speculatively due to failures on the cros trunk bot. But this CL
was not the cause of that problem, so I'm un-doing the revert.]

Currently, gyp attempts to autodetect whether the linker supports
the --icf flag.  It's more predictable to just require the caller
to specify whether they're using gold.

As a first demonstration of this, drop LINKER_USES_ICF code in the
Chrome build.  (I'll follow up with a gyp patch to remove the
LINKER_USES_ICF stuff in gyp.)

Review URL: https://chromiumcodereview.appspot.com/9368015

TBR=evan@chromium.org
Review URL: https://chromiumcodereview.appspot.com/9372012

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@121175 0039d316-1c4b-4281-b951-d872f2087c98

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