Audio: Preload MediaFoundation audio decoder library in Gpu process

Dolby's audio decoder for AC3,EC3 will be provided on windows as codec
package in next windows release, and libraries in those codec packages
will be signed by Dolby's certificate only. But
MediaFoundationAudioDecoder in chromium can initialize decoder library
with Microsoft signature only in sandboxed GPU process.

Dolby's library can not be signed by Microsoft, so we need a walkaround
to fix this problem.

Chromium GPU process is allowed to load some .dll files before it be
sandboxed. So we can load Dolby's library from MediaFoundation codec
package in that time.

And this problem is exist for other audio/video codecs too, they can add a little code to support their codecs.

BTW, this solution is from Microsoft.

Bug: 40884617
Change-Id: I6d3b6c7bd31b42601040d9ff88fef07d1dc4f512
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5373878


Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Commit-Queue: Sida Zhu <zhusida@bytedance.com>
Reviewed-by: Rafael Cintron <rafael.cintron@microsoft.com>
Cr-Commit-Position: refs/heads/main@{#1277253}