This fixes http://code.google.com/p/chromium/issues/detail?id=493, which was a crash in the 3dvia plugin. A script on the page tries to interact with the plugin by obtain its npobject. The plugin's does not implement the corresponding NPP_GetValue function correctly and returns NPERR_NO_ERROR  without filling in the NPObject pointer passed in. 
This fixes http://code.google.com/p/chromium/issues/detail?id=493, which
was a crash in the 3dvia plugin. A script on the page tries to interact
with the plugin by obtain its npobject. The plugin's does not implement the
corresponding NPP_GetValue function correctly and returns NPERR_NO_ERROR 
without filling in the NPObject pointer passed in. 

The fix is to initialize the NPObject pointer on the stack to NULL and check
for this along with the error check.

Review URL: http://codereview.chromium.org/212

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@1692 0039d316-1c4b-4281-b951-d872f2087c98

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