These tests for some guy's transparent operator functors were needlessly truncating their
double results to int. Preserving the doubleness makes compilers happier. I'm following
existing practice by adding an "// exact in binary" comment when the result isn't a whole number.
(The changes from 6 to 6.0 and so forth are stylistic, not critical.)
Fixes D27539.
git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@289106 91177308-0d34-0410-b5e6-96231b3b80d8