Revert of Roll chromium_revision 7b48b3e487..d1978b0eb8 (489906:490413) (patchset #1 id:1 of https://codereview.webrtc.org/2991983002/ )
Revert of Roll chromium_revision 7b48b3e487..d1978b0eb8 (489906:490413) (patchset #1 id:1 of https://codereview.webrtc.org/2991983002/ )

Reason for revert:
A change in a GN template breaks a downstream project. I am working on it.

Original issue's description:
> Roll chromium_revision 7b48b3e487..d1978b0eb8 (489906:490413)
>
> Change log: https://chromium.googlesource.com/chromium/src/+log/7b48b3e487..d1978b0eb8
> Full diff: https://chromium.googlesource.com/chromium/src/+/7b48b3e487..d1978b0eb8
>
> Changed dependencies:
> * src/base: https://chromium.googlesource.com/chromium/src/base/+log/dc18085af9..0c5d2b7e91
> * src/build: https://chromium.googlesource.com/chromium/src/build/+log/c2f466d88c..c2a01ae6b8
> * src/ios: https://chromium.googlesource.com/chromium/src/ios/+log/a124f02721..a31287f953
> * src/testing: https://chromium.googlesource.com/chromium/src/testing/+log/7383cd5ee3..eba9a70810
> * src/third_party: https://chromium.googlesource.com/chromium/src/third_party/+log/74bda1ad73..687a602b61
> * src/third_party/catapult: https://chromium.googlesource.com/external/github.com/catapult-project/catapult.git/+log/0f1f20d439..8b13c6e362
> * src/third_party/ffmpeg: https://chromium.googlesource.com/chromium/third_party/ffmpeg.git/+log/97ebed6795..a53b8db560
> * src/tools: https://chromium.googlesource.com/chromium/src/tools/+log/ba496e1820..d445995407
> DEPS diff: https://chromium.googlesource.com/chromium/src/+/7b48b3e487..d1978b0eb8/DEPS
>
> No update to Clang.
>
> TBR=
> BUG=None
>
> Review-Url: https://codereview.webrtc.org/2991983002
> Cr-Commit-Position: refs/heads/master@{#19182}
> Committed: https://chromium.googlesource.com/external/webrtc/+/9f0ef390f1d2126f2f35ce3ad75cac1d86b632bb

TBR=buildbot@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=None

Review-Url: https://codereview.webrtc.org/2987023003
Cr-Commit-Position: 972c6d2dc6dd5efdad1377c0d224e03eb8f276f7@{#19185}

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