These contributes to circular dependency problems in WebRTC
since one have to depend on webrtc.gyp in order to depend on
a target in them.
This reduces the number of cyclic dependencies in WebRTC from 21
to 16.
BUG=webrtc:4243
NOTRY=True
NOPRESUBMIT=True
Review URL: https://codereview.webrtc.org/1839763004
Cr-Commit-Position: refs/heads/master@{#12166}