Mechanical refactor to move ElementsKind type out of JSObject.

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 b570672f682e0abcffaa7713f6fa0f0799ec627a..d169bf6dfc61dcc14e6613a4ec15966dd81e58a9 100644
--- a/src/x64/lithium-x64.h
+++ b/src/x64/lithium-x64.h
@@ -1155,7 +1155,7 @@ class LLoadKeyedSpecializedArrayElement: public LTemplateInstruction<1, 2, 0> {
 
   LOperand* external_pointer() { return inputs_[0]; }
   LOperand* key() { return inputs_[1]; }
-  JSObject::ElementsKind elements_kind() const {
+  ElementsKind elements_kind() const {
     return hydrogen()->elements_kind();
   }
 };
@@ -1631,7 +1631,7 @@ class LStoreKeyedSpecializedArrayElement: public LTemplateInstruction<0, 3, 0> {
   LOperand* external_pointer() { return inputs_[0]; }
   LOperand* key() { return inputs_[1]; }
   LOperand* value() { return inputs_[2]; }
-  JSObject::ElementsKind elements_kind() const {
+  ElementsKind elements_kind() const {
     return hydrogen()->elements_kind();
   }
 };