Updating trunk VERSION from 3514.0 to 3515.0

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

Change-Id: I89ed1b22333f20f9d54100dbfb043dc0127f228f
Reviewed-on: https://chromium-review.googlesource.com/1163303Reviewed-by: chrome-release-bot@chromium.org <chrome-release-bot@chromium.org>
Cr-Commit-Position: refs/heads/master@{#580796}

chrome/VERSION

 MAJOR=70
 MINOR=0
-BUILD=3514
+BUILD=3515
 PATCH=0