Reland "Add dav1d decoder to WebRTC."

This reverts commit 8498b7e7f6b90fa036de2a6887d34256f0565b4f.

Reason for revert: Updating CL to include conditional build flag.

Original change's description:
> Revert "Add dav1d decoder to WebRTC."
>
> This reverts commit 147858577d4db6d257d3cc248fe571a1bbf887e3.
>
> Reason for revert: High binary size increase
>
> Original change's description:
> > Add dav1d decoder to WebRTC.
> >
> > Bug: none
> > Change-Id: I7642f42e592dcf510679f881f118bc4dab93b31c
> > Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/237504
> > Commit-Queue: Philip Eliasson <philipel@webrtc.org>
> > Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
> > Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
> > Reviewed-by: Magnus Flodman <mflodman@webrtc.org>
> > Reviewed-by: Sergey Silkin <ssilkin@webrtc.org>
> > Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
> > Cr-Commit-Position: refs/heads/main@{#35394}
>
> TBR=danilchap@webrtc.org,mbonadei@webrtc.org,ilnik@webrtc.org,philipel@webrtc.org,mflodman@webrtc.org,ssilkin@webrtc.org,webrtc-scoped@luci-project-accounts.iam.gserviceaccount.com
>
> Change-Id: I00a8acd6ea94ce523c2d5ba705333c9174678180
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: none
> Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/238560
> Reviewed-by: Artem Titov <titovartem@webrtc.org>
> Reviewed-by: Mirko Bonadei <mbonadei@webrtc.org>
> Owners-Override: Mirko Bonadei <mbonadei@webrtc.org>
> Owners-Override: Artem Titov <titovartem@webrtc.org>
> Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
> Cr-Commit-Position: refs/heads/main@{#35395}

# Not skipping CQ checks because original CL landed > 1 day ago.

Bug: none
Change-Id: Iff51848731646159e87e075c38af7cb6355f5b5b
Reviewed-on: https://webrtc-review.googlesource.com/c/src/+/238661
Reviewed-by: Danil Chapovalov <danilchap@webrtc.org>
Reviewed-by: Magnus Flodman <mflodman@webrtc.org>
Reviewed-by: Sergey Silkin <ssilkin@webrtc.org>
Reviewed-by: Philip Eliasson <philipel@webrtc.org>
Reviewed-by: Ilya Nikolaevskiy <ilnik@webrtc.org>
Commit-Queue: Philip Eliasson <philipel@webrtc.org>
Cr-Commit-Position: refs/heads/main@{#35409}
diff --git a/DEPS b/DEPS
index 64591e0..550a089 100644
--- a/DEPS
+++ b/DEPS
@@ -219,6 +219,8 @@
     'https://chromium.googlesource.com/chromium/deps/libjpeg_turbo.git@49836d72bd22c7a78bc0250483f04162278cdc6a',
   'src/third_party/libsrtp':
     'https://chromium.googlesource.com/chromium/deps/libsrtp.git@5b7c744eb8310250ccc534f3f86a2015b3887a0a',
+  'src/third_party/dav1d/libdav1d':
+    'https://chromium.googlesource.com/external/github.com/videolan/dav1d.git@692c0ce873d7d823f2255968e32b233d71d88b43',
   'src/third_party/libaom/source/libaom':
     'https://aomedia.googlesource.com/aom.git@b5719d38f3eb67e405b9fd7c90945f0a7ece10c0',
   'src/third_party/libunwindstack': {