Add virtual destructor to base class to resolve leak.
Add virtual destructor to base class to resolve leak.

This appears to resolve the regression that might have
been instigated in 44435.

This was very significant on Windows, as the derived
class held a lot of data in file_version_info_win.cc.

BUG=44320
r=mbelshe
Review URL: http://codereview.chromium.org/2131023

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@47964 0039d316-1c4b-4281-b951-d872f2087c98

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