Cut-off clang-format analysis.

If clang-format is confronted with long and deeply nested lines (e.g.
complex static initializers or function calls), it can currently try too
hard to find the optimal solution and never finish. The reason is that
the memoization does not work effectively for deeply nested lines.

This patch removes an earlier workaround and instead opts for
accepting a non-optimal solution in rare cases. However, it only does
so only in cases where it would have to analyze an excessive number of
states (currently set to 10000 - the most complex line in Format.cpp
requires ~800 states) so this should not change the behavior in a
relevant way.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@182449 91177308-0d34-0410-b5e6-96231b3b80d8