Convert some EXPECTs to ASSERTs to avoid crashes when object creation fails.

BUG=none
TEST=none
R=perkj@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/39649004

Cr-Commit-Position: refs/heads/master@{#8222}
git-svn-id: http://webrtc.googlecode.com/svn/trunk@8222 4adac7df-926f-26a2-2b94-8c16560cd09d
1 file changed