MediaCapabilities: Ship encrypted (EME) decodingInfo()

Intent thread:
https://groups.google.com/a/chromium.org/forum/?utm_medium=email&utm_source=footer#!msg/blink-dev/0yw8CuNaQEw/ppTxJme2EQAJ

Bug: 961885
Change-Id: I0b066a66288e00e27354a21d382500fe2dd838e5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1915824
Commit-Queue: Chrome Cunningham <chcunningham@chromium.org>
Reviewed-by: Philip Jägenstedt <foolip@chromium.org>
Auto-Submit: Chrome Cunningham <chcunningham@chromium.org>
Cr-Commit-Position: refs/heads/master@{#717946}
1 file changed