Mojo: Add leak detection to mojo::embedder::test::Shutdown().

mojo/system/embedder/test_embedder.cc

 // Copyright 2014 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 "mojo/system/embedder/test_embedder.h"
 
 #include "base/logging.h"
+#include "base/macros.h"
 #include "mojo/system/core_impl.h"
 
 namespace mojo {
+
+namespace system {
+namespace internal {
+
+bool ShutdownCheckNoLeaks(CoreImpl* core_impl) {
+  // No point in taking the lock.
+  if (core_impl->handle_table_.empty())
+    return true;
+
+  for (CoreImpl::HandleTableMap::const_iterator it =
+           core_impl->handle_table_.begin();
+       it != core_impl->handle_table_.end();
+       ++it) {
+    LOG(ERROR) << "Mojo embedder shutdown: Leaking handle " << (*it).first;
+  }
+  return false;
+}
+
+}  // namespace internal
+}  // namespace system
+
 namespace embedder {
 namespace test {
 
-void Shutdown() {
+bool Shutdown() {
   system::CoreImpl* core_impl = static_cast<system::CoreImpl*>(Core::Get());
   CHECK(core_impl);
   Core::Reset();
 
-  // TODO(vtl): Check for leaks, etc.
-
+  bool rv = system::internal::ShutdownCheckNoLeaks(core_impl);
   delete core_impl;
+  return rv;
 }
 
 }  // namespace test
 }  // namespace embedder
+
 }  // namespace mojo