Remove infinite recursion due to FileSpec change.
Remove infinite recursion due to FileSpec change.

Fixes infinite recursion due to change in how FileSpec deals with
removing the last path component.

Fixes timout for TestMiniDumpNew.py

git-svn-id: 4c4cc70b1ef44ba2b7963015e681894188cea27e@333666 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb,apple/swift-lldb,llvm-mirror/lldb,apple/swift-lldb,apple/swift-lldb,llvm-mirror/lldb