Revert "Fix test cases given Clang's improved location information."

The Clang improevments were reverted due to failures created in an asan
bootstrap.

This reverts commit r224387.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@224446 91177308-0d34-0410-b5e6-96231b3b80d8
[ASan] Move flag parsing logic to asan_flags.cc. NFC.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@224450 91177308-0d34-0410-b5e6-96231b3b80d8