Updating trunk VERSION from 4377.0 to 4378.0

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

Change-Id: Id0a4398c3d482b901fdf80d04c9bbd0e5d84514d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2606479Reviewed-by: Chrome Release Bot (LUCI) <chrome-official-brancher@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#839957}

chrome/VERSION

 MAJOR=89
 MINOR=0
-BUILD=4377
+BUILD=4378
 PATCH=0