Create WebRTC 70 branch for Chrome 70

TBR=

Change-Id: Ideb9b10552005b9d6fd0f34962732bc91eb3718a
Reviewed-on: https://webrtc-review.googlesource.com/96663
Reviewed-by: Olga Sharonova <olka@webrtc.org>
Cr-Commit-Position: refs/branch-heads/70@{open-webrtc-toolkit#1}
Cr-Branched-From: f18b352-refs/heads/master@{#24472}

tools_webrtc/whitespace.txt

@@ -13,3 +13,4 @@ Foo Bar Baz Bur
 
 Alios ego vidi ventos; alias prospexi animo procellas
   - Cicero
+.