update_engine: Remove WATCHLIST

This looks like an outdated file. I don't think there is any use of it at this
point. Removing!

BUG=none
TEST=none

Change-Id: Ieda1d491749190233a18ff57aa23072fa75ab3c2
Reviewed-on: https://chromium-review.googlesource.com/969075
Commit-Ready: Amin Hassani <ahassani@chromium.org>
Tested-by: Amin Hassani <ahassani@chromium.org>
Reviewed-by: Chirantan Ekbote <chirantan@chromium.org>
diff --git a/WATCHLISTS b/WATCHLISTS
deleted file mode 100644
index bcce0de..0000000
--- a/WATCHLISTS
+++ /dev/null
@@ -1,14 +0,0 @@
-# See http://dev.chromium.org/developers/contributing-code/watchlists for
-# a description of this file's format.
-# Please keep these keys in alphabetical order.
-
-{
-  'WATCHLIST_DEFINITIONS': {
-    'all': {
-      'filepath': '.',
-    },
-  },
-  'WATCHLISTS': {
-    'all': ['adlr@chromium.org', 'petkov@chromium.org']
-  },
-}