Updating trunk VERSION from 3596.0 to 3597.0

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

Change-Id: Ied5535100c5612069aeae967095b2c732f68c159
Reviewed-on: https://chromium-review.googlesource.com/c/1306642Reviewed-by: chrome-release-bot@chromium.org <chrome-release-bot@chromium.org>
Cr-Commit-Position: refs/heads/master@{#603765}

chrome/VERSION

 MAJOR=72
 MINOR=0
-BUILD=3596
+BUILD=3597
 PATCH=0