[frontend] -frewrite-includes: if there was no inclusion, don't add lineinfo that indicates return from another file.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179143 91177308-0d34-0410-b5e6-96231b3b80d8
[frontend] When preprocessing, turn implicit module imports into @imports.

part of rdar://13610250

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179144 91177308-0d34-0410-b5e6-96231b3b80d8
[frontend] -frewrite-includes: turn implicit module imports into @imports.

rdar://13610250

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179145 91177308-0d34-0410-b5e6-96231b3b80d8