MB-5308: don't load random doc until needed
MB-5308: don't load random doc until needed

Previously we would load it (due to eagerness of cell) on views
section. But we only need it when displaying some view.

Change-Id: I27b2dc88de14f3c40b5ca00d1842d9e5d07852b7
Reviewed-on: http://review.couchbase.org/19934
Tested-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>
Reviewed-by: Aliaksey Artamonau <3c875bcfb3adf2a65b2ae7686ca921e6c9433147@gmail.com>
Reviewed-by: Aliaksey Kandratsenka <340b8e09ca65cd3fc686427fcfed17e87eaf61e2@gmail.com>

membase/ns_server,daverigby/ns_server,nimishzynga/ns_server,vzasade/ns_server,daverigby/ns_server,mschoch/ns_server,ceejatec/ns_server,mschoch/ns_server,nimishzynga/ns_server,nimishzynga/ns_server,ceejatec/ns_server,vzasade/ns_server,membase/ns_server,pavel-blagodov/ns_server,mschoch/ns_server,vzasade/ns_server,mschoch/ns_server,t3rm1n4l/ns_server,ceejatec/ns_server,pavel-blagodov/ns_server,t3rm1n4l/ns_server,daverigby/ns_server,pavel-blagodov/ns_server,mschoch/ns_server,ceejatec/ns_server,membase/ns_server,nimishzynga/ns_server,t3rm1n4l/ns_server,nimishzynga/ns_server,nimishzynga/ns_server,mschoch/ns_server,t3rm1n4l/ns_server,ceejatec/ns_server,vzasade/ns_server,ceejatec/ns_server,membase/ns_server,membase/ns_server,daverigby/ns_server,t3rm1n4l/ns_server,daverigby/ns_server,membase/ns_server,pavel-blagodov/ns_server