We limit the number of candidates returned to Vim to 20 and also make sure that
we are not returning any duplicate candidates. This provides a noticeable
improvement in latency.
This makes the whole plugin much faster since we now don't need to serialize and
deserialize the return values from python funcs before we can use them in Vim.
Oh God I've been waiting for something like this for so long... using this also
forces us to demand vim 7.3.584 or higher.
First off, we don't block the GUI thread anymore for ClangCompleter (that was
always temporary). Secondly, now ClangCompleter will cache the data coming from
clang so that query-based filtering of members is fast.
This change was also the root cause of the crash bug I spent two days tracking
down. The problem was that the new bool member was not added to the custom copy
ctor... since we don't really need a custom copy ctor for Result, we're going
with the compiler-provided one.
This removes the need for a special overload for AddCandidatesToDatabase. Also,
the GetFuture function now provides a more sensible API with the list being
returned instead of accepted as an out parameter.
