Updating trunk VERSION from 3986.0 to 3987.0

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

Change-Id: Ic7ac716d80e755b4788ebec7ab47cd9ffeb21ef4
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1951585Reviewed-by: Chrome Release Bot (LUCI) <chrome-official-brancher@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#721846}

chrome/VERSION

 MAJOR=80
 MINOR=0
-BUILD=3986
+BUILD=3987
 PATCH=0