This was actually being done in 2 ways: via not saving the narrow in
the reload and second through calling `change_tab_to('#home')`. The
code is so ancient that it seems unlikely that this behavior was still
intentional.
Fixes part of #3687 (the remainder is fixed in a few commits).
This fixes the mobile web experience for Chrome on iOS.
Apparently, Chrome-on-iOS silently has a `viewport` module that
overrides and user-defined module by that name, causing all of our
code that accesses the viewport module to not work on that platform.
We fix this by renaming it.
Move recenter_pointer_on_display, suppress_scroll_pointer_update,
fast_forward_pointer, furthest_read, and server_furthest_read to
a new pointer module in pointer.js.