Add internal operation that converts a growable list to a fixed list.

runtime/vm/parser.cc

Index: runtime/vm/parser.cc
diff --git a/runtime/vm/parser.cc b/runtime/vm/parser.cc
index 2958e4798f00198a7041db0f02d686c0963e5ca0..6b43ee83ce8cc5085bb1cec18c618c7b9e32802c 100644
--- a/runtime/vm/parser.cc
+++ b/runtime/vm/parser.cc
@@ -5333,8 +5333,8 @@ void Parser::ParseNativeFunctionBlock(const ParamList* params,
   NativeFunction native_function = NativeEntry::ResolveNative(
       library, native_name, num_params, &auto_setup_scope);
   if (native_function == NULL) {
-    ErrorMsg(native_pos, "native function '%s' cannot be found",
-        native_name.ToCString());
+    ErrorMsg(native_pos, "native function '%s' (%d arguments) cannot be found",
+        native_name.ToCString(), func.NumParameters());
   }
   func.SetIsNativeAutoSetupScope(auto_setup_scope);