Migrated from the webm-tools repository with minor tweaks to
fix its build in the new location.
Last location/revision:
https://chromium.googlesource.com/webm/webm-tools
a7e97e8f0a913ddd97444392bb8816f44a4821a1
Change-Id: Icfad43d9fdd37fc413a6a28b57b370c97c7c28df
