[IndexedDB] Mojo testing harness.

content/browser/indexed_db/indexed_db_database_callbacks.h

 // 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.
 
 #ifndef CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_DATABASE_CALLBACKS_H_
 #define CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_DATABASE_CALLBACKS_H_
 
 #include <stdint.h>
 
 #include "base/macros.h"
@@ skipping 26 matching lines @@
       ::indexed_db::mojom::ObserverChangesPtr changes);
 
  protected:
   virtual ~IndexedDBDatabaseCallbacks();
 
  private:
   friend class base::RefCounted<IndexedDBDatabaseCallbacks>;
 
   class IOThreadHelper;
 
+  // Required for unittests so that are scheduled on a taskrunner.
+  struct DeleteOnIOThreadTaskRunner {
+    template <typename T>
+    static void Destruct(const T* x) {
+      if (!BrowserThread::DeleteSoon(BrowserThread::IO, FROM_HERE, x)) {
+#if defined(UNIT_TEST)
+        // Only logged under unit testing because leaks at shutdown
+        // are acceptable under normal circumstances.
+        LOG(ERROR) << "DeleteSoon failed on IO thread";
+#endif  // UNIT_TEST
+      }
+    }
+    template <typename T>
+    inline void operator()(T* ptr) const {
+      enum { type_must_be_complete = sizeof(T) };
+      Destruct(ptr);
+    }
+  };
+
   bool complete_ = false;
   scoped_refptr<IndexedDBContextImpl> indexed_db_context_;
-  std::unique_ptr<IOThreadHelper, BrowserThread::DeleteOnIOThread> io_helper_;
+  std::unique_ptr<IOThreadHelper, DeleteOnIOThreadTaskRunner> io_helper_;
   base::ThreadChecker thread_checker_;
 
   DISALLOW_COPY_AND_ASSIGN(IndexedDBDatabaseCallbacks);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_INDEXED_DB_INDEXED_DB_DATABASE_CALLBACKS_H_