[LSC] Add LOCAL_LICENSE_KINDS to external/libwebm am: a26f3396c1 am: db06ddaca6 am: 1e39c29b88 am: e0cd8697cf am: 3c91f29fce

Original change: https://android-review.googlesource.com/c/platform/external/libwebm/+/1588663

Change-Id: Ibce8d73348e32a9f12595a5f2bc34a6af9f30a0b