narrow: Hide loading indicators unconditionally before setting state.
narrow: Hide loading indicators unconditionally before setting state.

Before 77a26d41ae054c9d3c5d52ae2fbea5a4775cb2e4, there was only one
loading indicator (at the top of the page), so the if/else logic for
hiding loading indicators was correct, if confusing.  Since we've now
added a new bottom-of-page loading indicator, it's important to have
the logic correctly reset the state to hide all existing loading
indicators on narrowing, and then just render the ones needed/desired
by the current view.

Combined with similar code in `narrow.deactivate`, this achieves the
goal that we correctly update loading indicator state when switcing
views.

brainwane/zulip,brainwane/zulip,eeshangarg/zulip,brainwane/zulip,brainwane/zulip,kou/zulip,synicalsyntax/zulip,andersk/zulip,shubhamdhama/zulip,rht/zulip,kou/zulip,synicalsyntax/zulip,timabbott/zulip,shubhamdhama/zulip,andersk/zulip,punchagan/zulip,shubhamdhama/zulip,rht/zulip,hackerkid/zulip,rht/zulip,brainwane/zulip,punchagan/zulip,punchagan/zulip,eeshangarg/zulip,timabbott/zulip,rht/zulip,showell/zulip,synicalsyntax/zulip,rht/zulip,kou/zulip,kou/zulip,punchagan/zulip,kou/zulip,timabbott/zulip,hackerkid/zulip,timabbott/zulip,showell/zulip,showell/zulip,zulip/zulip,hackerkid/zulip,synicalsyntax/zulip,eeshangarg/zulip,zulip/zulip,hackerkid/zulip,punchagan/zulip,zulip/zulip,eeshangarg/zulip,synicalsyntax/zulip,shubhamdhama/zulip,synicalsyntax/zulip,eeshangarg/zulip,zulip/zulip,timabbott/zulip,shubhamdhama/zulip,punchagan/zulip,synicalsyntax/zulip,andersk/zulip,showell/zulip,rht/zulip,brainwane/zulip,zulip/zulip,timabbott/zulip,shubhamdhama/zulip,eeshangarg/zulip,zulip/zulip,kou/zulip,brainwane/zulip,eeshangarg/zulip,hackerkid/zulip,andersk/zulip,showell/zulip,shubhamdhama/zulip,hackerkid/zulip,zulip/zulip,showell/zulip,rht/zulip,kou/zulip,andersk/zulip,punchagan/zulip,andersk/zulip,showell/zulip,timabbott/zulip,hackerkid/zulip,andersk/zulip