[turbofan] Improve JSON output

test/cctest/compiler/test-graph-visualizer.cc

Index: test/cctest/compiler/test-graph-visualizer.cc
diff --git a/test/cctest/compiler/test-graph-visualizer.cc b/test/cctest/compiler/test-graph-visualizer.cc
index ce3e6b71e99f4c8abe47d1c6a5801a923ae8fc48..0798c18b540403dfea783bebf2ce61fe5a37e9cf 100644
--- a/test/cctest/compiler/test-graph-visualizer.cc
+++ b/test/cctest/compiler/test-graph-visualizer.cc
@@ -14,6 +14,7 @@
 #include "src/compiler/operator.h"
 #include "src/compiler/schedule.h"
 #include "src/compiler/scheduler.h"
+#include "src/compiler/source-position.h"
 #include "src/compiler/verifier.h"
 
 using namespace v8::internal;
@@ -33,7 +34,7 @@ TEST(NodeWithNullInputReachableFromEnd) {
 
   OFStream os(stdout);
   os << AsDOT(graph);
-  os << AsJSON(graph);
+  os << AsJSON(graph, new SourcePositionTable(&graph));
 }
 
 
@@ -51,7 +52,7 @@ TEST(NodeWithNullControlReachableFromEnd) {
 
   OFStream os(stdout);
   os << AsDOT(graph);
-  os << AsJSON(graph);
+  os << AsJSON(graph, new SourcePositionTable(&graph));
 }
 
 
@@ -69,7 +70,7 @@ TEST(NodeWithNullInputReachableFromStart) {
 
   OFStream os(stdout);
   os << AsDOT(graph);
-  os << AsJSON(graph);
+  os << AsJSON(graph, new SourcePositionTable(&graph));
 }
 
 
@@ -86,5 +87,5 @@ TEST(NodeWithNullControlReachableFromStart) {
 
   OFStream os(stdout);
   os << AsDOT(graph);
-  os << AsJSON(graph);
+  os << AsJSON(graph, new SourcePositionTable(&graph));
 }