Incrementing VERSION to 78.0.3904.99

TBR=kariah@chromium.org

Change-Id: I60105c5efdebf60b3b2287eff9d9b87932120bde
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1902769
Reviewed-by: Chrome Release Bot (LUCI) <chrome-official-brancher@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/branch-heads/3904@{#861}
Cr-Branched-From: 675968a8c657a3bd9c1c2c20c5d2935577bbc5e6-refs/heads/master@{#693954}
1 file changed