Change cc::ElementId to be a uint64_t

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

Index: third_party/WebKit/Source/core/dom/DOMNodeIds.cpp
diff --git a/third_party/WebKit/Source/core/dom/DOMNodeIds.cpp b/third_party/WebKit/Source/core/dom/DOMNodeIds.cpp
index c638646e95ebb6dcd9d9248672baa674eebb32e4..a3fb870c41b47033a44772951aae70168d1d1a06 100644
--- a/third_party/WebKit/Source/core/dom/DOMNodeIds.cpp
+++ b/third_party/WebKit/Source/core/dom/DOMNodeIds.cpp
@@ -8,16 +8,18 @@
 
 namespace blink {
 
-DEFINE_WEAK_IDENTIFIER_MAP(Node);
+DEFINE_WEAK_IDENTIFIER_MAP(Node, uint64_t);
 
 // static
-int DOMNodeIds::IdForNode(Node* node) {
-  return WeakIdentifierMap<Node>::Identifier(node);
+uint64_t DOMNodeIds::IdForNode(Node* node) {
+  uint64_t retval = WeakIdentifierMap<Node, uint64_t>::Identifier(node);
+  DCHECK_GT(retval, 0ull);
+  return retval;
 }
 
 // static
-Node* DOMNodeIds::NodeForId(int id) {
-  return WeakIdentifierMap<Node>::Lookup(id);
+Node* DOMNodeIds::NodeForId(uint64_t id) {
+  return WeakIdentifierMap<Node, uint64_t>::Lookup(id);
 }
 
 }  // namespace blink