Previously Java 8 bytecode was transpiled into Java 7 bytecode for AAR. With this change we instead include Java 8 bytecode in the AAR. This drops support for Java 7 but allows using Java 8 features such as static methods in interfaces and default methods. Bug: webrtc:8084, chromium:762967 Change-Id: I3c6ec9332c5612b7ed811a81957f25c94c80da70 No-Try: True Reviewed-on: https://webrtc-review.googlesource.com/21222 Commit-Queue: Sami Kalliomäki <sakal@webrtc.org> Reviewed-by: Magnus Jedvert <magjed@webrtc.org> Cr-Commit-Position: refs/heads/master@{#20849}