swift234

[+0 self] Remove fix lifetime from FunctionSignature Opts.

With the improvements I have made to the ARC optimizer, these are no longer
necessary. This will give us an idea if guaranteed is being respected properly
without enabling +0 self.

The main effect that this could cause are use-after-frees. I checked with guard
malloc and asan that we are not performing any use-after-frees on the
PerfTestSuite and asan with ninja check.

Swift SVN r25654