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 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.
llvm also has a copy of gtest in its source tree. This causes cmake to bork
since it sees several different targets with the same name (gtest and
gtest_main). So we have to rename our versions of gtest and gtest_main to
something else... We're just appending _ycm now.
This will cause pain when we want to update gtest in the future from upstream,
but I don't see a better way of handling this.
The problem was that should have been using a longest common subsequence
algorithm for the "number of word boundary character matches" calculation. Our
old approach would fail for the following case:
Query: "caafoo"
Candidate1 : "acaaCaaFooGxx"
Candidate2 : "aCaafoog"
Candidate1 needs to win. This is now also a test case.
The point is that we want to prefer candidates that have the query characters
"earlier" in their text, e.g. "xxabcxxx" over "xxxxxabc" for "abc" query.
