<rdar://problem/12537646>

lldb remembers not-found source file, setting target.source-map doesn't make it re-check for it. Now this is fixed. Each time the source path remappings get updated, the modification ID in the PathMappingList gets bumped and then we know the re-check for sources.



git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@177125 91177308-0d34-0410-b5e6-96231b3b80d8