DO NOT MERGE Do not require signed zero support in ldexp tests()

This relaxes ldexp() tests to allow -0/+0 to be interchanged.

Bug: 19145770
Change-Id: I46c6a8f224606a15be0f974af36c281612f2398b
(cherry picked from commit 1e44f197ded674677381f65c840820728cf36efb)
1 file changed