Updating trunk VERSION from 6648.0 to 6649.0

* This is an automated release commit.
* Do not revert without consulting chrome-pmo@google.com.
NOAUTOREVERT=true

Change-Id: Id82502c30de9de9b3a244b0d231eda5cd6c70528
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5778899
Bot-Commit: Chrome Release Bot (LUCI) <chrome-official-brancher@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#1340004}

chrome/VERSION

 MAJOR=129
 MINOR=0
-BUILD=6648
+BUILD=6649
 PATCH=0