Header hygiene: remove using directive and #undef DEBUG_TYPE once we're done.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@214263 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Analysis/RegionInfoImpl.h

@@ -25,7 +25,7 @@
 #include <iterator>
 #include <set>
 
-using namespace llvm;
+namespace llvm {
 
 #define DEBUG_TYPE "region"
 
@@ -916,4 +916,8 @@ void RegionInfoBase<Tr>::calculate(FuncT &F) {
   buildRegionsTree(DT->getNode(BB), TopLevelRegion);
 }
 
+#undef DEBUG_TYPE
+
+} // end namespace llvm
+
 #endif