Add some missing #includes for GCC mainline, patch by Shantonu Sen!


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@48153 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/AST/CFG.cpp b/AST/CFG.cpp
index f571e4e..da8159c 100644
--- a/AST/CFG.cpp
+++ b/AST/CFG.cpp
@@ -25,7 +25,7 @@
 #include <iomanip>
 #include <algorithm>
 #include <sstream>
-
+#include <iostream>
 
 using namespace clang;