Updating trunk VERSION from 4237.0 to 4238.0

# This is an automated release commit.
# Do not revert without consulting chrome-pmo@google.com.
NOAUTOREVERT=true
TBR=srinivassista@chromium.org

Change-Id: Idde01476544d3ec2227a4fb82ba9db558b7f20b6
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2360949Reviewed-by: Chrome Release Bot (LUCI) <chrome-official-brancher@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#798971}

chrome/VERSION

 MAJOR=86
 MINOR=0
-BUILD=4237
+BUILD=4238
 PATCH=0