Make 'webrtc' target a complete static library on Linux, Android and Windows
Make 'webrtc' target a complete static library on Linux, Android and Windows

It's currently not possible on Mac and iOS due to libtool. See webrtc:6418
for more info.

BUG=webrtc:6418
NOTRY=True

Review-Url: https://codereview.webrtc.org/2367313002
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#16411}

TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc,TimothyGu/libilbc,ShiftMediaProject/libilbc,TimothyGu/libilbc