A few days ago we blogged about the issue with OBIEE and Chrome update 30.
For those using 18.104.22.168.x please upgrade to latest patchset.
The fix is included in 22.214.171.124.10 and above (so in 126.96.36.199.11, 188.8.131.52.12 automatically).
This is also explained in KM article:
OBIEE 11g: Chrome 30 and Pop-up Windows not Displayed
Doc ID 1590991.1