Bindings for injectable Java video encoders.

BUG=webrtc:7760

Review-Url: https://codereview.webrtc.org/3003873002
Cr-Original-Commit-Position: refs/heads/master@{#19651}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 07a3bd7c4b54399e2abd4713619427f9638ab6d9
17 files changed