Revert of Bump up scaling limit for MediaCodec. (patchset #3 id:40001 of https://codereview.webrtc.org/2566533002/ )

Reason for revert:
Failed on the perf tests.

Original issue's description:
> Bump up scaling limit for MediaCodec.
>
> Wait until MediaCodec is better tested at these low
> resolutions, and until some fallback mechanism is in place
> before lowering this threshold.
>
> BUG=webrtc:6837
>
> Committed: https://crrev.com/3e9b1330467edf6b5af609b375c15efb9e6b4933
> Cr-Commit-Position: refs/heads/master@{#15498}

TBR=magjed@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6837

Review-Url: https://codereview.webrtc.org/2562963002
Cr-Original-Commit-Position: refs/heads/master@{#15500}
Cr-Mirrored-From: https://chromium.googlesource.com/external/webrtc
Cr-Mirrored-Commit: 1cd0a0ab43846072b1e2f37c953ecd770feb5963
2 files changed