Bug 1330791 - Enable the no-cond-assign rule for eslint in /services. There are no associated errors with enabling this rule. r=markh

MozReview-Commit-ID: BM83kDZJpZ3

--HG--
extra : rebase_source : 3769dc72cfe5d0b328926d94bd7d45fc4d02a215

services/.eslintrc.js

@@ -9,7 +9,6 @@ module.exports = {
        until they get fixed, at which point their
        respective line in this file should be removed. */
     "consistent-return": "warn",
-    "no-cond-assign": "warn",
     "no-ex-assign": "warn",
     "no-func-assign": "warn",
     "no-native-reassign": "warn",