Updating trunk VERSION from 3506.0 to 3507.0

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

Change-Id: Ib9e20055672b7c44bef0ba00106dd3b7017c49cd
Reviewed-on: https://chromium-review.googlesource.com/1154352Reviewed-by: chrome-release-bot@chromium.org <chrome-release-bot@chromium.org>
Cr-Commit-Position: refs/heads/master@{#578946}

chrome/VERSION

 MAJOR=70
 MINOR=0
-BUILD=3506
+BUILD=3507
 PATCH=0