[Merge to M44] Chromium changes to statically link ffmpeg.

1. Eliminates a large number of windows crashes hit while loading the DLL (see bugs)
2. Reducing the size of binary (about 400KB on linux, about 265KB on 32bit windows) due to dead-code elimination
3. Simplifying media library initialization (Remove bool-ness, it just works)

We've audited all the licenses for the files we actually use and have the green light from legal as long as we include the license text in the credits.

TBR=thomasvl@chromium.org, dalecurtis@chromium.org, enne@chromium.org, grt@chromium.org, gunsch@chromium.org, isherman@chromium.org, jamiewalch@chromium.org, jochen@chromium.org, maruel@chromium.org, mmoss@google.com, phajdan.jr@chromium.org, sergeyu@chromium.org, sky@chromium.org
BUG=435455, 429131, 441908

Original Review URL:

(cherry picked from commit fd11b3c3aa6730ae1f024811b61913cd63f9d39a - refs/heads/master@{#333423})

Review URL: https://codereview.chromium.org/1179953006.

Cr-Commit-Position: refs/branch-heads/2403@{#342}
Cr-Branched-From: f54b8097a9c45ed4ad308133d49f05325d6c5070-refs/heads/master@{#330231}
63 files changed