Change cc::ElementId to be a uint64_t

third_party/WebKit/Source/core/dom/DOMNodeIds.h

Index: third_party/WebKit/Source/core/dom/DOMNodeIds.h
diff --git a/third_party/WebKit/Source/core/dom/DOMNodeIds.h b/third_party/WebKit/Source/core/dom/DOMNodeIds.h
index 15bb91f13db1d45355d55d7538b2e146338e8bcd..9396f50d2358bdc432f1a477b37b2c2470e85f52 100644
--- a/third_party/WebKit/Source/core/dom/DOMNodeIds.h
+++ b/third_party/WebKit/Source/core/dom/DOMNodeIds.h
@@ -12,14 +12,16 @@
 
 namespace blink {
 
-DECLARE_WEAK_IDENTIFIER_MAP(Node);
+DECLARE_WEAK_IDENTIFIER_MAP(Node, uint64_t);
+
+using DOMNodeId = uint64_t;
 
 class CORE_EXPORT DOMNodeIds {
   STATIC_ONLY(DOMNodeIds);
 
  public:
-  static int IdForNode(Node*);
-  static Node* NodeForId(int id);
+  static DOMNodeId IdForNode(Node*);
+  static Node* NodeForId(DOMNodeId);
 };
 
 }  // namespace blink