When we trace to file, add eol of each trace message.
When we trace to file, add eol of each trace message.

BUG=webrtc:4864
TEST=Manual Test with voe_cmd_test
R=pbos@webrtc.org
TBR=kjellander@webrtc.org

The regression is introduced in #8529, Review URL: https://webrtc-codereview.appspot.com/34329004.

Review URL: https://codereview.webrtc.org/1256773002 .

Cr-Original-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#9644}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: a44660960a24c5167ad4b8b15093d577dfc224b0

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