Revert "Roll src/third_party/dav1d/libdav1d/ 296d1dc00..d398da88c (9 commits)"

This reverts commit ae8d84f1.

Reason for revert: https://crbug.com/1057531

Original change's description:
> Roll src/third_party/dav1d/libdav1d/ 296d1dc00..d398da88c (9 commits)
>
> https://chromium.googlesource.com/external/github.com/videolan/dav1d.git/+log/296d1dc00641..d398da88c0b6
>
> $ git log 296d1dc00..d398da88c --date=short --no-merges --format='%ad %ae %s'
> 2020-02-17 janne-vlc fuzzing: link the fuzzing binaries as C++
> 2020-02-17 janne-vlc fuzzing: split the fuzzing targets to their own meson.build file
> 2020-02-20 gramner x86: Add mc w_mask 4:4:4 AVX-512 (Ice Lake) asm
> 2020-02-20 gramner x86: Add mc w_mask 4:2:2 AVX-512 (Ice Lake) asm
> 2020-02-20 gramner x86: Add mc w_mask 4:2:0 AVX-512 (Ice Lake) asm
> 2020-02-20 gramner x86: Add mc avg/w_avg/mask AVX-512 (Ice Lake) asm
> 2020-02-14 victorien x86: optimize cdef_filter_{4x{4,8},8x8}_avx2
> 2020-02-12 victorien x86: add a seperate fully edged case to cdef_filter_avx2
> 2020-02-19 gramner checkasm: Improve the cdef input randomization algorithm
>
> Created with:
>   roll-dep src/third_party/dav1d/libdav1d
>
> TBR=tguilbert
>
> Change-Id: Ic1389410c6338ad343bfdffb132e8f4a38960845
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2080893
> Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
> Reviewed-by: Thomas Guilbert <tguilbert@chromium.org>
> Commit-Queue: Dale Curtis <dalecurtis@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#745691}

BUG=1057531
TBR=dalecurtis@chromium.org,tguilbert@chromium.org

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

Change-Id: Ica0528ded63a977c649760d9eadabea9495d5f8f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2083604Reviewed-by: Thomas Guilbert <tguilbert@chromium.org>
Reviewed-by: Dale Curtis <dalecurtis@chromium.org>
Commit-Queue: Dale Curtis <dalecurtis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#746215}

DEPS

@@ -753,7 +753,7 @@ deps = {
     Var('chromium_git') + '/angle/angle.git' + '@' +  Var('angle_revision'),
 
   'src/third_party/dav1d/libdav1d':
-    Var('chromium_git') + '/external/github.com/videolan/dav1d.git' + '@' + 'd398da88c0b68e3dbb966256c7ed682b211579e3',
+    Var('chromium_git') + '/external/github.com/videolan/dav1d.git' + '@' + '296d1dc006419546f342606ff7d47564bd9798a8',
 
   'src/third_party/dawn':
     Var('dawn_git') + '/dawn.git' + '@' +  Var('dawn_revision'),