Release scriptable object reference when deleting WebPluginDelegateProxy.
Release scriptable object reference when deleting WebPluginDelegateProxy.

BUG=87660
TEST=Open multiple tabs each of which embeds the same NPAPI plugin.  Close each tab one by one, and verify that each instance's scriptable object is torn down when the instance is destroyed as a result of the tab closing, rather than when all the tabs have closed.


Review URL: http://codereview.chromium.org/7259011

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@90699 0039d316-1c4b-4281-b951-d872f2087c98

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