Incrementing VERSION to 73.0.3683.15

TBR=benmason@chromium.org

Change-Id: I9e644d18b44369e236a9a534e77c6a439bfc6c1a
Reviewed-on: https://chromium-review.googlesource.com/c/1449375
Reviewed-by: chrome-release-bot@chromium.org <chrome-release-bot@chromium.org>
Cr-Commit-Position: refs/branch-heads/3683@{#103}
Cr-Branched-From: e51029943e0a38dd794b73caaf6373d5496ae783-refs/heads/master@{#625896}
diff --git a/chrome/VERSION b/chrome/VERSION
index 2df64fc..d895fc4 100644
--- a/chrome/VERSION
+++ b/chrome/VERSION
@@ -1,4 +1,4 @@
 MAJOR=73
 MINOR=0
 BUILD=3683
-PATCH=14
+PATCH=15