Add a method to convert unsigned C integer into V8 Integer.

include/v8.h

Index: include/v8.h
===================================================================
--- include/v8.h	(revision 3009)
+++ include/v8.h	(working copy)
@@ -1063,6 +1063,7 @@
 class V8EXPORT Integer : public Number {
  public:
   static Local<Integer> New(int32_t value);
+  static inline Local<Integer> New(uint32_t value);
   int64_t Value() const;
   static inline Integer* Cast(v8::Value* obj);
  private:
@@ -3026,6 +3027,16 @@
 }
 
 
+Local<Integer> Integer::New(uint32_t value) {
+  // If highest bit is not set, chances are it's SMI.
+  bool could_be_smi = (value & (1 << 31)) == 0;
+  if (could_be_smi) {
+    return Integer::New(static_cast<int32_t>(value));
+  }
+  return Local<Integer>::Cast(Number::New(value));
+}
+
+
 Integer* Integer::Cast(v8::Value* value) {
 #ifdef V8_ENABLE_CHECKS
   CheckCast(value);