Improve compile error when invoking OnceCallback::Run on a non-rvalue.

base/bind_unittest.nc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // This is a "No Compile Test" suite.
 // http://dev.chromium.org/developers/testing/no-compile-tests
 
 #include <utility>
 
 #include "base/bind.h"
@@ skipping 206 matching lines @@
   OnceClosure cb2 = BindOnce(std::move(cb));
 }
 
 #elif defined(NCTEST_DISALLOW_BINDING_REPEATING_CALLBACK_WITH_NO_ARGS)  // [r"static_assert failed \"Attempting to bind a base::Callback with no additional arguments: save a heap allocation and use the original base::Callback object\""]
 
 void WontCompile() {
   Closure cb = Bind([] {});
   Closure cb2 = Bind(cb);
 }
 
+#elif defined(NCTEST_DISALLOW_ONCECALLBACK_RUN_ON_LVALUE)  // [r"static_assert failed \"OnceCallback::Run\(\) may only be invoked on an rvalue, i\.e\. std::move\(callback\)\.Run\(\)\.\""]
+
+void WontCompile() {
+  OnceClosure cb = Bind([] {});
+  cb.Run();

[dcheng, 2016/11/19 08:07:59]

I could put this in callback_unittest.nc as well, but it feels weird to put in a
test case that's invalid for multiple reasons (since it's invalid to call Run()
on an unbound callback).

+}
+
 #endif
 
 }  // namespace base