Updating trunk VERSION from 4287.0 to 4288.0

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

Change-Id: I63c1953958510d34850c8369be168c7360ddef8d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2461800Reviewed-by: Chrome Release Bot (LUCI) <chrome-official-brancher@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#815461}

chrome/VERSION

 MAJOR=88
 MINOR=0
-BUILD=4287
+BUILD=4288
 PATCH=0