Use a const rather than macro for EcDefault.

- This should be a better solution to the build error in
  https://webrtc-codereview.appspot.com/425005
- Ideally all of the similar macros should go away, but one thing at
  a time...

BUG=
TEST=voe_auto_test

Review URL: https://webrtc-codereview.appspot.com/438002

git-svn-id: http://webrtc.googlecode.com/svn/trunk@1860 4adac7df-926f-26a2-2b94-8c16560cd09d
4 files changed