Add a -rewrite-includes option, which is similar to -rewrite-macros, but only expands #include directives.

Patch contributed by Lubos Lunak (l.lunax@suse.cz).
Review by Matt Beaumont-Gay (matthewbg@google.com).

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@158093 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/FrontendTool/ExecuteCompilerInvocation.cpp b/lib/FrontendTool/ExecuteCompilerInvocation.cpp
index f72d294..d4e47ba 100644
--- a/lib/FrontendTool/ExecuteCompilerInvocation.cpp
+++ b/lib/FrontendTool/ExecuteCompilerInvocation.cpp
@@ -73,6 +73,7 @@
   case PrintPreamble:          return new PrintPreambleAction();
   case PrintPreprocessedInput: return new PrintPreprocessedAction();
   case RewriteMacros:          return new RewriteMacrosAction();
+  case RewriteIncludes:        return new RewriteIncludesAction();
   case RewriteObjC:            return new RewriteObjCAction();
   case RewriteTest:            return new RewriteTestAction();
   case RunAnalysis:            return new ento::AnalysisAction();