Remove the dependency of Zone on Isolate

test/cctest/compiler/test-representation-change.cc

Index: test/cctest/compiler/test-representation-change.cc
diff --git a/test/cctest/compiler/test-representation-change.cc b/test/cctest/compiler/test-representation-change.cc
index a96859b0493f55cd262f7a429952240a12a7aed9..f44648e651594577d67067f885ad3024ac2d85b4 100644
--- a/test/cctest/compiler/test-representation-change.cc
+++ b/test/cctest/compiler/test-representation-change.cc
@@ -25,7 +25,8 @@ class RepresentationChangerTester : public HandleAndZoneScope,
   explicit RepresentationChangerTester(int num_parameters = 0)
       : GraphAndBuilders(main_zone()),
         javascript_(main_zone()),
-        jsgraph_(main_graph_, &main_common_, &javascript_, &main_machine_),
+        jsgraph_(main_isolate(), main_graph_, &main_common_, &javascript_,
+                 &main_machine_),
         changer_(&jsgraph_, &main_simplified_, main_isolate()) {
     Node* s = graph()->NewNode(common()->Start(num_parameters));
     graph()->SetStart(s);