- Allow for loading dart:html and friends into the standalone

runtime/bin/builtin_natives.cc

Index: runtime/bin/builtin_natives.cc
diff --git a/runtime/bin/builtin_natives.cc b/runtime/bin/builtin_natives.cc
index 96280df35da2e5d4ed42bc5609da48581b70649d..dc6ee178879cd38966a7fc3896d3fe475c11a71e 100644
--- a/runtime/bin/builtin_natives.cc
+++ b/runtime/bin/builtin_natives.cc
@@ -44,6 +44,12 @@ static struct NativeEntries {
 };
 
 
+void Builtin_DummyNative(Dart_NativeArguments args) {
+  UNREACHABLE();
+}
+
+
+
 /**
  * Looks up native functions in both libdart_builtin and libdart_io.
  */
@@ -51,8 +57,8 @@ Dart_NativeFunction Builtin::NativeLookup(Dart_Handle name,
                                           int argument_count,
                                           bool* auto_setup_scope) {
   const char* function_name = NULL;
-  Dart_Handle result = Dart_StringToCString(name, &function_name);
-  DART_CHECK_VALID(result);
+  Dart_Handle err = Dart_StringToCString(name, &function_name);
+  DART_CHECK_VALID(err);
   ASSERT(function_name != NULL);
   ASSERT(auto_setup_scope != NULL);
   *auto_setup_scope = true;
@@ -64,7 +70,12 @@ Dart_NativeFunction Builtin::NativeLookup(Dart_Handle name,
       return reinterpret_cast<Dart_NativeFunction>(entry->function_);
     }
   }
-  return IONativeLookup(name, argument_count, auto_setup_scope);
+  Dart_NativeFunction result =
+      IONativeLookup(name, argument_count, auto_setup_scope);
+  if (result == NULL) {
+    result = Builtin_DummyNative;
+  }
+  return result;
 }