Refactor ASTReader::readInputFileInfo to return a struct containing the related information.

No functionality change.

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@203881 91177308-0d34-0410-b5e6-96231b3b80d8
[Modules] Make sure that the synthesized file "__inferred_module.map" doesn't show up as dependency of a module file.

Follow-up for rdar://15459210

git-svn-id: http://llvm.org/svn/llvm-project/cfe/trunk@203882 91177308-0d34-0410-b5e6-96231b3b80d8