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..3f00ba7a2c42117640ec36168a409f1f9400d089 100644
--- a/third_party/WebKit/Source/core/dom/DOMNodeIds.h
+++ b/third_party/WebKit/Source/core/dom/DOMNodeIds.h
@@ -12,14 +12,14 @@
 
 namespace blink {
 
-DECLARE_WEAK_IDENTIFIER_MAP(Node);
+DECLARE_WEAK_IDENTIFIER_MAP(Node, unsigned long long);
 
 class CORE_EXPORT DOMNodeIds {
   STATIC_ONLY(DOMNodeIds);
 
  public:
-  static int IdForNode(Node*);
-  static Node* NodeForId(int id);
+  static unsigned long long IdForNode(Node*);

[suzyh_UTC10 (ex-contributor), 2017/05/05 04:27:30]

Is this "unsigned long long" different from the ElementId "unsigned long long"?
If not, why not use ElementId here?

[chrishtr, 2017/05/05 05:34:52]

It's different from ElementId, because:
* ElementId is a conceptual encoding of primary and secondary keys.
* DOMNodeIds has more than one consumer (OffscreenCanvas is another).

+  static Node* NodeForId(unsigned long long id);
 };
 
 }  // namespace blink