Check for a passed-in type argument vector in the prolog of generic functions.

runtime/vm/native_entry.h

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #ifndef RUNTIME_VM_NATIVE_ENTRY_H_
 #define RUNTIME_VM_NATIVE_ENTRY_H_
 
 #include "platform/memory_sanitizer.h"
 
 #include "vm/allocation.h"
@@ skipping 35 matching lines @@
 #define TRACE_NATIVE_CALL(format, name)                                        \
   do {                                                                         \
   } while (0)
 #endif
 
 #define NATIVE_ENTRY_FUNCTION(name) BootstrapNatives::DN_##name
 
 #ifdef DEBUG
 #define SET_NATIVE_RETVAL(args, value)                                         \
   RawObject* retval = value;                                                   \
-  ASSERT(retval->IsDartInstance());                                            \
+  ASSERT(retval->IsDartInstance() || retval->IsTypeArguments());               \
   arguments->SetReturnUnsafe(retval);
 #else
 #define SET_NATIVE_RETVAL(arguments, value) arguments->SetReturnUnsafe(value);
 #endif
 
 #define DEFINE_NATIVE_ENTRY(name, argument_count)                              \
   static RawObject* DN_Helper##name(Isolate* isolate, Thread* thread,          \
                                     Zone* zone, NativeArguments* arguments);   \
   void NATIVE_ENTRY_FUNCTION(name)(Dart_NativeArguments args) {                \
     CHECK_STACK_ALIGNMENT;                                                     \
@@ skipping 83 matching lines @@
   static void AutoScopeNativeCallWrapperNoStackCheck(Dart_NativeArguments args,
                                                      Dart_NativeFunction func);
 
   static bool ReturnValueIsError(NativeArguments* arguments);
   static void PropagateErrors(NativeArguments* arguments);
 };
 
 }  // namespace dart
 
 #endif  // RUNTIME_VM_NATIVE_ENTRY_H_