Add reverse file remapping for breakpoint set

LLDB can remap a source file to a new directory based on the
"target.sorce-map" to handle the usecase when the source code moved
between the compliation and the debugging. Previously the remapping
was only used to display the content of the file. This CL fixes the
scenario when a breakpoint is set based on the new an absolute path
with adding an inverse remapping step before looking up the breakpoint
location.

Differential revision: http://reviews.llvm.org/D17848

llvm-svn: 262711