Consolidate anonymous namespace content and file-static methods to all be in the anonymous namespace, in preparation for refactoring a few of the functions a little.
Consolidate anonymous namespace content and file-static methods to all be in the
anonymous namespace, in preparation for refactoring a few of the functions a
little.

No code change.

BUG=none
TEST=none
R=henrik.lundin@webrtc.org, tina.legrand@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/36949004

Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 4dba2e98a2b248e85e6acc08a9e517ea170c487e

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