Add v8::Value::IsRegExp method.

src/api.cc

Index: src/api.cc
diff --git a/src/api.cc b/src/api.cc
index adeced54b5fe1a043ddfee55f92d4a1193ffc565..4bd5699c000cfacfe76276cfbada39426f52fde4 100644
--- a/src/api.cc
+++ b/src/api.cc
@@ -1792,6 +1792,13 @@ bool Value::IsDate() const {
 }
 
 
+bool Value::IsRegExp() const {
+  if (IsDeadCheck("v8::Value::IsRegExp()")) return false;
+  i::Handle<i::Object> obj = Utils::OpenHandle(this);
+  return obj->IsJSRegExp();
+}
+
+
 Local<String> Value::ToString() const {
   if (IsDeadCheck("v8::Value::ToString()")) return Local<String>();
   LOG_API("ToString");