FileEntry: Remove unused and half-broken copy ctor.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@202893 91177308-0d34-0410-b5e6-96231b3b80d8
[C++11] Push move semantics through APValue.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@202894 91177308-0d34-0410-b5e6-96231b3b80d8