The function narrow.unparse() is used in a bunch of places in
the search suggestion code, and now it no longer lower cases
operands. This change contributes to fixing trac #1659.
(imported from commit 6b44b8a818482b5c8b4f9a45bc7d3a9d21e04eba)
Streams are converted to their "official" names now.
Topics are not canonicalized at all.
All other operands continue to be lowercased.
Since we don't lowercase stream/topic at the parsing stage,
we have to modify the predicate function to do the lowercasing
of stream/topic to enable case-insensitive comparisons. This
is slightly more expensive. The server-side predicate
functions are already case-insensitive.
(imported from commit 286f118c6c3ff9d23b37c7f958cab4c0eacd5feb)
If we have a stream named "Denmark" and we're narrowed to it,
then use "Denmark" as the default stream name in the compose box
even if the narrow operators are lowercase.
(imported from commit e9f06b7307c73231aa887dc95849e0307984e6f0)
1) The class Filter now lives in its own module.
2) The function canonicalized_operators() is now a class method on Filter.
3) The function message_in_home moved to filter.js and became private.
4) Various calling code had to change, of course.
5) Splitting out Filter helped simplify a few tests.
(imported from commit e41d792b46d3d6a30d3bd03db0419f129d0a2a7b)
There are also one or two places we don't need to use it for security
purposes, but we do so for consistencey.
(imported from commit aa111f5a22a0e8597ec3cf8504adae66d5fb6768)
