Invert arguments to ASSERT_EQ to match gtest diagnostic printing

GTest assumes the left hand side of the assert is the expectation and
the right hand side is the test result. It's easier to read gtest
failures when these things are ordered correctly.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@192854 91177308-0d34-0410-b5e6-96231b3b80d8