Fix r276671 to not use a defaulted move constructor.

MSVC won't provide the body of this move constructor and assignment
operator, possibly because the copy constructor is banned. Just write
it manually.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@276685 91177308-0d34-0410-b5e6-96231b3b80d8
1 file changed