Adds a function to run FrontendActions over in-memory code. This is
the first step towards a standalone Clang tool infrastructure.
The plan is to make it easy to build command line tools that run over
the AST of source files in a project outside of the build system.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@129924 91177308-0d34-0410-b5e6-96231b3b80d8
6 files changed