Put all LLVM code into the llvm namespace, as per bug 109.

llvm-svn: 9903
diff --git a/llvm/include/Support/GraphTraits.h b/llvm/include/Support/GraphTraits.h
index 305f71e2..4ff7417 100644
--- a/llvm/include/Support/GraphTraits.h
+++ b/llvm/include/Support/GraphTraits.h
@@ -18,6 +18,8 @@
 #ifndef SUPPORT_GRAPHTRAITS_H
 #define SUPPORT_GRAPHTRAITS_H
 
+namespace llvm {
+
 // GraphTraits - This class should be specialized by different graph types...
 // which is why the default version is empty.
 //
@@ -76,4 +78,6 @@
   inline Inverse(GraphType &G) : Graph(G) {}
 };
 
+} // End llvm namespace
+
 #endif