scoped_refptr: support opaque pointed-to classes via extern template

base/memory/ref_counted_unittest.cc

 // Copyright (c) 2012 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.
 
 #include "base/memory/ref_counted.h"
+
+#include "base/test/opaque_ref_counted.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
 
 class SelfAssign : public base::RefCounted<SelfAssign> {
   friend class base::RefCounted<SelfAssign>;
 
   ~SelfAssign() {}
 };
 
@@ skipping 37 matching lines @@
 TEST(RefCountedUnitTest, ScopedRefPtrMemberAccess) {
   CheckDerivedMemberAccess check;
 }
 
 TEST(RefCountedUnitTest, ScopedRefPtrToSelf) {
   ScopedRefPtrToSelf* check = new ScopedRefPtrToSelf();
   EXPECT_FALSE(ScopedRefPtrToSelf::was_destroyed());
   check->SelfDestruct();
   EXPECT_TRUE(ScopedRefPtrToSelf::was_destroyed());
 }
+
+TEST(RefCountedUnitTest, ScopedRefPtrToOpaque) {
+  scoped_refptr<base::OpaqueRefCounted> p = base::MakeOpaqueRefCounted();
+  base::TestOpaqueRefCounted(p);
+
+  scoped_refptr<base::OpaqueRefCounted> q;
+  q = p;
+  base::TestOpaqueRefCounted(p);
+  base::TestOpaqueRefCounted(q);
+}