Changing the hash to "#" causes Chrome to jump to the top of the page
on Mac OS X. This commit doesn't actually fix any bug, but it
is necessary for my *next* commit, where otherwise you'd have to
ensure that the scroll code came *after* the hashchange code.
(imported from commit 925b44d770c96dafaabebc9e0114f9a3b8f53c4d)