Define convenient FATAL_ERROR() and FATAL_ERROR_IF() macros
Define convenient FATAL_ERROR() and FATAL_ERROR_IF() macros

R=henrike@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/16079004

Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 0fa6366ed15f48b3ec227987f21f339180fb4936

sippet/webrtc,sippet/webrtc,sippet/webrtc,sippet/webrtc,sippet/webrtc,sippet/webrtc