Echo: Make overlay dismiss only if you click *outside* it.
Echo: Make overlay dismiss only if you click *outside* it.

Change-Id: Ifa099fa2d9ccf77a66cb45d39a52c7dbfd0f229d

wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo,wikimedia/mediawiki-extensions-Echo