[Driver] Refactor clang driver to use LLVM's Option library

The big changes are:
- Deleting Driver/(Arg|Opt)*
- Rewriting includes to llvm/Option/ and re-sorting
- 'using namespace llvm::opt' in clang::driver
- Fixing the autoconf build by adding option everywhere

As discussed in the review, this change includes using directives in
header files.  I'll make follow up changes to remove those in favor of
name specifiers.

Reviewers: espindola

Differential Revision: http://llvm-reviews.chandlerc.com/D975

llvm-svn: 183989

clang/lib/Frontend/CreateInvocationFromCommandLine.cpp

@@ -13,15 +13,16 @@
 
 #include "clang/Frontend/Utils.h"
 #include "clang/Basic/DiagnosticOptions.h"
-#include "clang/Driver/ArgList.h"
 #include "clang/Driver/Compilation.h"
 #include "clang/Driver/Driver.h"
 #include "clang/Driver/Options.h"
 #include "clang/Driver/Tool.h"
 #include "clang/Frontend/CompilerInstance.h"
 #include "clang/Frontend/FrontendDiagnostic.h"
+#include "llvm/Option/ArgList.h"
 #include "llvm/Support/Host.h"
 using namespace clang;
+using namespace llvm::opt;
 
 /// createInvocationFromCommandLine - Construct a compiler invocation object for
 /// a command line argument vector.
@@ -76,7 +77,7 @@ clang::createInvocationFromCommandLine(ArrayRef<const char *> ArgList,
     return 0;
   }
 
-  const driver::ArgStringList &CCArgs = Cmd->getArguments();
+  const ArgStringList &CCArgs = Cmd->getArguments();
   OwningPtr<CompilerInvocation> CI(new CompilerInvocation());
   if (!CompilerInvocation::CreateFromArgs(*CI,
                                      const_cast<const char **>(CCArgs.data()),