Add two nodes to the call graph:
 - Root is the main function or 0.
 - ExternalCallingNode has edges to all external functions.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@76876 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/tools/wpa/clang-wpa.cpp b/tools/wpa/clang-wpa.cpp
index dff8cb0b..e7515ec 100644
--- a/tools/wpa/clang-wpa.cpp
+++ b/tools/wpa/clang-wpa.cpp
@@ -65,5 +65,5 @@
   for (unsigned i = 0, e = TUnits.size(); i != e; ++i)
     CG->addTU(*(TUnits[i]->AST));
 
-  CG->dump();
+  CG->ViewCallGraph();
 }