[Sanitizer] Fix a bug introduced in r196112. Add a test.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@196263 91177308-0d34-0410-b5e6-96231b3b80d8
[Sanitizer] Use more appropriate InternalScopedString in GetCodeRangeForFile

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@196264 91177308-0d34-0410-b5e6-96231b3b80d8