CodeStubs contain their corresponding Isolate* now. (part 2)

src/x64/stub-cache-x64.cc

Index: src/x64/stub-cache-x64.cc
diff --git a/src/x64/stub-cache-x64.cc b/src/x64/stub-cache-x64.cc
index 2b9f9746066be86005222ebd93b1cc8577edefc6..3fe64acafded40407fa8f9107b940a3bd66f47f1 100644
--- a/src/x64/stub-cache-x64.cc
+++ b/src/x64/stub-cache-x64.cc
@@ -944,13 +944,13 @@ void LoadStubCompiler::GenerateLoadField(Register reg,
                        field.is_inobject(holder),
                        field.translate(holder),
                        representation);
-    GenerateTailCall(masm(), stub.GetCode(isolate()));
+    GenerateTailCall(masm(), stub.GetCode());
   } else {
     KeyedLoadFieldStub stub(isolate(),
                             field.is_inobject(holder),
                             field.translate(holder),
                             representation);
-    GenerateTailCall(masm(), stub.GetCode(isolate()));
+    GenerateTailCall(masm(), stub.GetCode());
   }
 }