When a function handling an event doesn't return a value, it leaves the "event" object on the global context. This namespace pollution was causing some functionality that was trying to detect if we were in an event, such as popup blocking, to go wrong.
When a function handling an event doesn't return a value, it leaves
the "event" object on the global context. This namespace pollution
was causing some functionality that was trying to detect if we were
in an event, such as popup blocking, to go wrong.

BUG=6367
Review URL: http://codereview.chromium.org/18013

git-svn-id: de016e52bd170d2d4f2344f9bf92d50478b649e0@8050 0039d316-1c4b-4281-b951-d872f2087c98

gavinp/chromium,ropik/chromium,gavinp/chromium,ropik/chromium,yitian134/chromium,adobe/chromium,adobe/chromium,yitian134/chromium,ropik/chromium,gavinp/chromium,adobe/chromium,gavinp/chromium,yitian134/chromium,adobe/chromium,ropik/chromium,yitian134/chromium,Crystalnix/house-of-life-chromium,adobe/chromium,adobe/chromium,Crystalnix/house-of-life-chromium,gavinp/chromium,Crystalnix/house-of-life-chromium,Crystalnix/house-of-life-chromium,gavinp/chromium,yitian134/chromium,adobe/chromium,ropik/chromium,yitian134/chromium,adobe/chromium,Crystalnix/house-of-life-chromium,adobe/chromium,yitian134/chromium,Crystalnix/house-of-life-chromium,Crystalnix/house-of-life-chromium,gavinp/chromium,ropik/chromium,gavinp/chromium,yitian134/chromium,ropik/chromium,Crystalnix/house-of-life-chromium,Crystalnix/house-of-life-chromium,yitian134/chromium,Crystalnix/house-of-life-chromium,Crystalnix/house-of-life-chromium,ropik/chromium,adobe/chromium,gavinp/chromium,yitian134/chromium,ropik/chromium,adobe/chromium,gavinp/chromium