Make the clang-fuzzer use the CompilerInstance directly.

Going through the driver is too slow.

llvm-svn: 233459
diff --git a/clang/lib/Tooling/Tooling.cpp b/clang/lib/Tooling/Tooling.cpp
index 60371fb..e100003 100644
--- a/clang/lib/Tooling/Tooling.cpp
+++ b/clang/lib/Tooling/Tooling.cpp
@@ -90,7 +90,7 @@
 }
 
 /// \brief Returns a clang build invocation initialized from the CC1 flags.
-static clang::CompilerInvocation *newInvocation(
+clang::CompilerInvocation *newInvocation(
     clang::DiagnosticsEngine *Diagnostics,
     const llvm::opt::ArgStringList &CC1Args) {
   assert(!CC1Args.empty() && "Must at least contain the program name!");