Do not add values to HGraph in Lithium.

src/x64/lithium-x64.h

Index: src/x64/lithium-x64.h
diff --git a/src/x64/lithium-x64.h b/src/x64/lithium-x64.h
index 717a07ab7a5ef0838771df76e1a80749d311cb2c..a84f9406972198b0fa503f8199dca0c171ceb494 100644
--- a/src/x64/lithium-x64.h
+++ b/src/x64/lithium-x64.h
@@ -92,6 +92,7 @@ class LCodeGen;
   V(DoubleToSmi)                                \
   V(Drop)                                       \
   V(DummyUse)                                   \
+  V(Dummy)                                      \
   V(ElementsKind)                               \
   V(ForInCacheArray)                            \
   V(ForInPrepareMap)                            \
@@ -423,6 +424,13 @@ class LLazyBailout V8_FINAL : public LTemplateInstruction<0, 0, 0> {
 };
 
 
+class LDummy V8_FINAL : public LTemplateInstruction<1, 0, 0> {
+ public:
+  explicit LDummy() { }
+  DECLARE_CONCRETE_INSTRUCTION(Dummy, "dummy")
+};
+
+
 class LDummyUse V8_FINAL : public LTemplateInstruction<1, 1, 0> {
  public:
   explicit LDummyUse(LOperand* value) {